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Hypothesis #9
Evolution
Sam has to make a decision, and either way she’s going to lose.
Samantha is still reeling from her discovery about Andreas and is questioning everything she thought she knew about her former best friend. Before she can figure out what to do, Sam makes another shocking discovery, this time about what really happened between her father and the Kristiansens over fifteen years ago.
Sam is faced with two impossible decisions.
Unfortunately, no matter what she decides, she’s going to lose.
‘EVOLUTION’ is the final book (book 3) in the ‘Fundamentals of Biology’ trilogy and cannot be read as a standalone. ‘Fundamentals of Biology’ is the third trilogy in a series of trilogies that begins with ‘Elements of Chemistry’ and ‘Laws of Physics.’ You do NOT need to read ‘Elements of Chemistry’ or ‘Laws of Physics’ before reading ‘Fundamentals of Biology.
Samantha is still reeling from her discovery about Andreas and is questioning everything she thought she knew about her former best friend. Before she can figure out what to do, Sam makes another shocking discovery, this time about what really happened between her father and the Kristiansens over fifteen years ago.
Sam is faced with two impossible decisions.
Unfortunately, no matter what she decides, she’s going to lose.
‘EVOLUTION’ is the final book (book 3) in the ‘Fundamentals of Biology’ trilogy and cannot be read as a standalone. ‘Fundamentals of Biology’ is the third trilogy in a series of trilogies that begins with ‘Elements of Chemistry’ and ‘Laws of Physics.’ You do NOT need to read ‘Elements of Chemistry’ or ‘Laws of Physics’ before reading ‘Fundamentals of Biology.
248 pages, Paperback
First published November 6, 2025
134 people are currently reading
6635 people want to read
About the author
Penny Reid
92 books22.5k followersSign up for the newsletter of awesome: www.pennyreid.ninja/newsletter
Penny Reid is the New York Times, Wall Street Journal, and USA Today bestselling author of the Winston Brothers and Knitting in the City series. She used to spend her days writing federal grant proposals as a biomedical researcher, but now she writes kissing books. Penny is an obsessive knitter and manages the #OwnVoices-focused mentorship incubator / publishing imprint, Smartypants Romance. She lives in Seattle Washington with her husband, three kids, and dog named Hazel.
FOLLOW PENNY:
Facebook: www.facebook.com/pennyreidwriter
Twitter: www.twitter.com/reidromance
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Penny Reid is the New York Times, Wall Street Journal, and USA Today bestselling author of the Winston Brothers and Knitting in the City series. She used to spend her days writing federal grant proposals as a biomedical researcher, but now she writes kissing books. Penny is an obsessive knitter and manages the #OwnVoices-focused mentorship incubator / publishing imprint, Smartypants Romance. She lives in Seattle Washington with her husband, three kids, and dog named Hazel.
FOLLOW PENNY:
Facebook: www.facebook.com/pennyreidwriter
Twitter: www.twitter.com/reidromance
Instagram:www.instagram.com/reidromance
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November 6, 2025
The wait is finally over! Part 3 of the Fundamentals of Biology trilogy, EVOLUTION is now available everywhere across the internets! The trilogy is complete, go forth and read!
Tropes
Fake Dating
Plot with multiple twists
Women in STEM
She’s morally grey
He’s morally grey too…
Forced Proximity
Former childhood friends to lovers
READ Part 1 INHERITANCE: https://geni.us/InheritancePR
READ Part 2 REPRODUCTION: https://geni.us/ReproductionPR
READ Part 3 EVOLUTION: https://geni.us/EvolutionPR
READ the Bundled Edition: https://geni.us/FOBPRShop
**BLURB**
Sam has to make a decision, and either way she’s going to lose.
Samantha is still reeling from her discovery about Andreas and is questioning everything she thought she knew about her former best friend. Before she can figure out what to do, Sam makes another shocking discovery, this time about what really happened between her father and the Kristiansens over fifteen years ago.
Sam is faced with two impossible decisions.
Unfortunately, no matter what she decides, she’s going to lose.
‘EVOLUTION’ is the final book (book 3) in the ‘Fundamentals of Biology’ trilogy and cannot be read as a standalone. ‘Fundamentals of Biology’ is the third trilogy in a series of trilogies that begins with ‘Elements of Chemistry’ and ‘Laws of Physics.’ You do NOT need to read ‘Elements of Chemistry’ or ‘Laws of Physics’ before reading ‘Fundamentals of Biology.
December 30, 2025
truly devastated to be giving an PR book 3 stars. just know that her 3 stars are still better than anyone else's, but this was definitely one of my least favorites of hers so far 😭
rtc
rtc
November 10, 2025
Super satisfying end to the trilogy. This plot was bananas and I was there for it the whole way. I can always count on Penny Reid to teach me something (at least a few new words and this time inheritance law) while building impeccable characters.
November 6, 2025
I never doubted that Penny could redeem Andreas, and she did it in such a way that really fit into his character.
There is so much that goes on in this final book, and it really was a journey for Samantha and Andreas. The fact that it took time for the trust to be built back, and that Kaitlyn had to really spell it out, full circle moment.
So much of the storyline is wrapped up, and though we’re left with some things still up in the air, the reader will be left with hope, and of course an HEA.
I loved the cameos, and I especially loved how much we got to see Martin and Kaitlyn through all three installments.
There is so much that goes on in this final book, and it really was a journey for Samantha and Andreas. The fact that it took time for the trust to be built back, and that Kaitlyn had to really spell it out, full circle moment.
So much of the storyline is wrapped up, and though we’re left with some things still up in the air, the reader will be left with hope, and of course an HEA.
I loved the cameos, and I especially loved how much we got to see Martin and Kaitlyn through all three installments.
November 29, 2025
A bit of a dragged plot, but the side characters were fun to follow. The hero had layers; the heroine had the ability to be present in scenes. Unfortunately, romance requires more than attendance. I still had a somewhat decent time with it, but the rushed ending and complete lack of a proper epilogue was an unforgivable choice. I just wanted a simple look at where they end up, but the story cut out right when it mattered most.
November 6, 2025
God, the Penny Reid book hangovers are the worst. I just want to live inside her stories and worlds, they are too delicious.
It was a long three week wait to finally read the third act of Sam & Andreas’ story, but my God did she nail it.
Now I’m on a countdown to ‘Prom King’ in December so I can get my next Penny Reid hit.
It was a long three week wait to finally read the third act of Sam & Andreas’ story, but my God did she nail it.
Now I’m on a countdown to ‘Prom King’ in December so I can get my next Penny Reid hit.
January 12, 2026
The ending of the series was good, but it dragged a bit.
I like Penny Reid's style. The novels in the Hypothesis series aren't my favorites by the author, but I enjoy them.
[3-3.5 stars]
I like Penny Reid's style. The novels in the Hypothesis series aren't my favorites by the author, but I enjoy them.
[3-3.5 stars]
November 15, 2025
The whole series should have been one book. The ending was extremely underwhelming, and Sam was actually so annoying by the end of it.
I liked that we got to know Andreas’ character in a deeper level but I still felt there was not much substance to the storyline and Penny was pushing it.
I liked that we got to know Andreas’ character in a deeper level but I still felt there was not much substance to the storyline and Penny was pushing it.
November 13, 2025
(Review for all three biology books)
𝘽𝙖𝙙 𝙨𝙮𝙣𝙤𝙥𝙨𝙞𝙨
A chess grandmaster takes extreme measures to make a scientist call him daddy
𝙂𝙤𝙤𝙙 𝙨𝙩𝙪𝙛𝙛
Unputdownable
Chemistry
The sheer intelligence behind it all
𝘽𝙖𝙙 𝙨𝙩𝙪𝙛𝙛
Henrik
Nieminen
𝙏𝙧𝙤𝙥𝙚𝙨/𝙨𝙪𝙗 𝙜𝙚𝙣𝙧𝙚𝙨
Enemies to lovers
Fake dating
Woman in STEM
Male virgin
𝙊𝙫𝙚𝙧𝙖𝙡𝙡 𝙩𝙝𝙤𝙪𝙜𝙝𝙩𝙨
Samantha is a crazy smart scientist with a fairly tragic childhood. She’s always felt justice wasn’t served to the man who destroyed her family. So when super hot chess grandmaster Andreas (evil family destroyer’s youngest son and her former childhood bestie) approaches her with an idea to get her father’s company shares back, her interest is piqued.
Now, I am not an unintelligent woman, but I am not a biologist, nor a lover of chess. And although I adore that nothing was dumbed down - because that wouldn’t have been realistic - parts of reading the first book was somewhat akin to being in a conversation with people that have inside jokes and you-had-to-be-there stories. Amusing in the way it’s told, but some of it being lost on me.
Andreas was intense and stoic and had definitely been in love with Sam his whole life. The way he always thought 27467 steps ahead was mind boggling.
Sam was a dichotomy - science grad student too busy to remember to shower, but also a former law student who dressed to kill.
Nieminen was absolutely vile. I don’t want to spoil anything with my thoughts of what I expected to happen but…he was just vile.
I loved the way both Andreas and Sam’s minds worked. They were both so freaking smart but in different ways. I loved the side characters, I loved the chemistry, I loved that Sam was the experienced one, I loved that Andreas genuinely didn’t think the way most other people do and that we got to see his reasoning for some of his decisions, I loved the cameos from the other science trilogies, I loved. It. All.
What I didn’t love? That it ended. Because I didn’t want to leave this world that Penny built.
𝙍𝙖𝙩𝙞𝙣𝙜𝙨
🤤🤤🤤🤤
💦💦💦
🤣🤣🤣
😭😭
🌟🌟🌟🌟🌟
𝘽𝙖𝙙 𝙨𝙮𝙣𝙤𝙥𝙨𝙞𝙨
A chess grandmaster takes extreme measures to make a scientist call him daddy
𝙂𝙤𝙤𝙙 𝙨𝙩𝙪𝙛𝙛
Unputdownable
Chemistry
The sheer intelligence behind it all
𝘽𝙖𝙙 𝙨𝙩𝙪𝙛𝙛
Henrik
Nieminen
𝙏𝙧𝙤𝙥𝙚𝙨/𝙨𝙪𝙗 𝙜𝙚𝙣𝙧𝙚𝙨
Enemies to lovers
Fake dating
Woman in STEM
Male virgin
𝙊𝙫𝙚𝙧𝙖𝙡𝙡 𝙩𝙝𝙤𝙪𝙜𝙝𝙩𝙨
Samantha is a crazy smart scientist with a fairly tragic childhood. She’s always felt justice wasn’t served to the man who destroyed her family. So when super hot chess grandmaster Andreas (evil family destroyer’s youngest son and her former childhood bestie) approaches her with an idea to get her father’s company shares back, her interest is piqued.
Now, I am not an unintelligent woman, but I am not a biologist, nor a lover of chess. And although I adore that nothing was dumbed down - because that wouldn’t have been realistic - parts of reading the first book was somewhat akin to being in a conversation with people that have inside jokes and you-had-to-be-there stories. Amusing in the way it’s told, but some of it being lost on me.
Andreas was intense and stoic and had definitely been in love with Sam his whole life. The way he always thought 27467 steps ahead was mind boggling.
Sam was a dichotomy - science grad student too busy to remember to shower, but also a former law student who dressed to kill.
Nieminen was absolutely vile. I don’t want to spoil anything with my thoughts of what I expected to happen but…he was just vile.
I loved the way both Andreas and Sam’s minds worked. They were both so freaking smart but in different ways. I loved the side characters, I loved the chemistry, I loved that Sam was the experienced one, I loved that Andreas genuinely didn’t think the way most other people do and that we got to see his reasoning for some of his decisions, I loved the cameos from the other science trilogies, I loved. It. All.
What I didn’t love? That it ended. Because I didn’t want to leave this world that Penny built.
𝙍𝙖𝙩𝙞𝙣𝙜𝙨
🤤🤤🤤🤤
💦💦💦
🤣🤣🤣
😭😭
🌟🌟🌟🌟🌟
November 11, 2025
“I love you, Samantha. I love you so much.”I smiled into his hair, feeling a rush of something fierce and unnameable. “I know,” I whispered. “I know.”
I didn’t need or want to qualify it. I didn’t wish to hedge or joke or run away. I let myself be loved. And it was the best, worst, and most terrifying thing I’d ever done.
my my, she did it again. can't say i enjoyed the first book in the trilogy that much but the other two? man, I'm down bad. for Andreas. lol
And when he was discussing sex related things with Sam, it was like reading about Mona from Laws of physics trilogy. damn, i miss mona and abram. it didn't reach their level. but i enjoyed it.
January 19, 2026
Penny Reid writes amazing and interesting love stories. You have something trite as a “fake engagement” premise and she turned it into a heartfelt romance with funny secondary characters, lovey cameos from previous series, and deep/tortured yet loving main characters. Their love is not insta, and it’s not just from the past. It grows, and strengthens while the series progresses.
I love how she always makes a point to show how emotional intelligence is so important in life, and that IQ needs to be balanced with some feelings.
I have no complaints with the audio, narrator does a great job at portraying the “aloofness” of FMC.
I love how she always makes a point to show how emotional intelligence is so important in life, and that IQ needs to be balanced with some feelings.
I have no complaints with the audio, narrator does a great job at portraying the “aloofness” of FMC.
November 11, 2025
I was so sad at the end of book two when things fell apart for Sam and Andreas. His sexy innocence and her sinical-related barriers were coming together for an epic romance. Then it all fell apart because people don’t communicate!!! Time lapses a few sad months and then they’re bumping into each other and Andreas is proving, again, that he can be counted on and that he knows Sam better than she knows herself. All this is done in typical Penny Reid style – witty characters, emotional scenes, a bit of drama and of course, science. I love this author. I honestly don’t think she can write a bad story. 5 stars for the conclusion of this story.
November 13, 2025
She never disappoints me
I always love reading a Penny Reid book(s). These are my reward for doing my chores. I read these three books in record time. 4 days. My place is small and not that clean. I cheated on occasion. LOL 😆 I've just about read them all. I love them all. I can't wait for the next.
I always love reading a Penny Reid book(s). These are my reward for doing my chores. I read these three books in record time. 4 days. My place is small and not that clean. I cheated on occasion. LOL 😆 I've just about read them all. I love them all. I can't wait for the next.
November 18, 2025
Was not expecting this to become an action adventure, but I loved every second of it!
So definitely be re-reading it again!
So definitely be re-reading it again!
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December 4, 2025
2.5 stars rounded up bc 2 feels too mean…I did generally like this book I guess but it was lacking for me. The whole series overall wasn’t great.
Some pet peeves: after trashing her grandpa for 2 books she all the sudden is talking to him, loves him and he’s an integral part of the plot…convenient, but there was no conversation on page to hash out the fucked up past and no mention of it ever happening. What happened to him abandoning you as a teenager? Divorcing his wife a month after her cancer diagnosis ESPECIALLY given the fact they were the sole caregivers for her, their orphaned granddaughter. Literally unforgivable to put that end of life care and stress on an orphaned teenager then leave her on her own in life. Then he remarried immediately, no mention of that lady in this book. PENNY: we needed a fucking argument about this at the very least!! Wtf. Seemed like her strategy was like: grandpa shows up after a decade and he’s a sweet old man and he’s sorry but he never really says it and so our h goes from no contact I hate him to aww look at that sad old man, I’ll forget and just embrace him bc look he’s so old. Oh and if I don’t I have no family member for my long term plan in this book (I won’t spoil lol).
Similarly I feel that Andreas was forgiven with no real conversation about it. It was built up and then pretty anticlimactic he can’t figure out an apology is essential on his own. So instead of a confrontation it’s just this slow fade out of hate and anger into love with no real conversations just circumstance and oops we’re making out again I guess we’re dating now, right? Right. Idk I just didn’t like it.
I also didn’t love Sam’s martyr situation at the end with the shares. That was annoying.
The climax of the danger in this book was overly villainous and silly imo and given how much protection Sam, etc had I feel like this possibility should’ve been foreseen and prevented. Sending Sam into that situation was also insane.
Anyway, I do feel like they’re kind of cute so it wasn’t a total hate fest. I love seeing Martin and Kaitlyn and their little baby. They actually played a rather large part in this book bc of Kaitlyn’s mysterious illness. I also like Sam’s friends mostly. The original trilogies in this series I loved at the time so I was excited for more installments. Penny was my first intro to science-y romances but unfortunately at this point there’s a new queen in town and it’s Ali Hazelwood 🫢 sorry but she does academia romance better 😩 I also would’ve loved some more chess heavy plot *cough*Ali Hazelwood*cough* 👀😅 sorry again. And overall this book was easy to put down. For instance I literally stopped reading last night with just the last few pages of the epilogue left 😅 so clearly I don’t care about these people very much. This was alright but PR reads are pretty hit or miss for me these days, unfortunate.
Some pet peeves: after trashing her grandpa for 2 books she all the sudden is talking to him, loves him and he’s an integral part of the plot…convenient, but there was no conversation on page to hash out the fucked up past and no mention of it ever happening. What happened to him abandoning you as a teenager? Divorcing his wife a month after her cancer diagnosis ESPECIALLY given the fact they were the sole caregivers for her, their orphaned granddaughter. Literally unforgivable to put that end of life care and stress on an orphaned teenager then leave her on her own in life. Then he remarried immediately, no mention of that lady in this book. PENNY: we needed a fucking argument about this at the very least!! Wtf. Seemed like her strategy was like: grandpa shows up after a decade and he’s a sweet old man and he’s sorry but he never really says it and so our h goes from no contact I hate him to aww look at that sad old man, I’ll forget and just embrace him bc look he’s so old. Oh and if I don’t I have no family member for my long term plan in this book (I won’t spoil lol).
Similarly I feel that Andreas was forgiven with no real conversation about it. It was built up and then pretty anticlimactic he can’t figure out an apology is essential on his own. So instead of a confrontation it’s just this slow fade out of hate and anger into love with no real conversations just circumstance and oops we’re making out again I guess we’re dating now, right? Right. Idk I just didn’t like it.
I also didn’t love Sam’s martyr situation at the end with the shares. That was annoying.
The climax of the danger in this book was overly villainous and silly imo and given how much protection Sam, etc had I feel like this possibility should’ve been foreseen and prevented. Sending Sam into that situation was also insane.
Anyway, I do feel like they’re kind of cute so it wasn’t a total hate fest. I love seeing Martin and Kaitlyn and their little baby. They actually played a rather large part in this book bc of Kaitlyn’s mysterious illness. I also like Sam’s friends mostly. The original trilogies in this series I loved at the time so I was excited for more installments. Penny was my first intro to science-y romances but unfortunately at this point there’s a new queen in town and it’s Ali Hazelwood 🫢 sorry but she does academia romance better 😩 I also would’ve loved some more chess heavy plot *cough*Ali Hazelwood*cough* 👀😅 sorry again. And overall this book was easy to put down. For instance I literally stopped reading last night with just the last few pages of the epilogue left 😅 so clearly I don’t care about these people very much. This was alright but PR reads are pretty hit or miss for me these days, unfortunate.
January 1, 2026
I thought this was only a relatively satisfying ending. Why not “entirely satisfying”? Well, there are just too many questions and unsettling thoughts left in my head!
1) Andreas has this strange reaction when learning of the gossip of he and Roman being in a relationship. What was the wince for? I thought we were going to get a hot side-story where Andreas did some “exploring” with Roman. Didn’t have to be major, but some heavy petting would have been hot. lol
2) We’re told Andreas doesn’t get along with Nakita (towards the end of the book as Sam recovers), but never really told why. Is it just because of the time she super fanned him, or because Sam warned him that she publicizes everything she hears? Or did she maybe make a pass at him when they met for coffee?? Did they even MEET for coffee???
3) We NEED MORE ANDREAS. One tiny chapter from the male perspective was not enough. I don’t know why Reid even bothered stating which character’s POV carries each chapter, but the fact she did was frustrating. It never changed and that just made me hope it would! I seriously hope Reid issues another book of this same story but from Andreas’ POV. There might have been a total of two chapters from Andreas throughout the 3-book series now that I think of it. Again, NOT nearly enough. We need some “splaining” please!
4) There’s a point in this book where Sam is explaining to Andreas who has been staying with her to keep her safe from sleepwalking. She says things like “…my friend Diya”, and “my former roommate Nakita…”. WHY!?? Andreas knows these women personally. He’s had dinner, drinks, conversations, etc. with them all. It’s odd. Reid must have written this early on and forgotten to go back and correct? If they’re for the new reader, she shouldn’t bother since nobody can really start fresh at this 3rd book without having read the first two.
5) What happens to the darned shares!? We get some sexy times at the very end (thank GOD, because we readers have waited through 3 full books for Andreas to get his due!) but nothing about the company is wrapped up.
6) Another HUGE question that never gets answered is why Grampa Carl left Sam’s grandma right after her cancer diagnosis. I was certain we’d get the backstory and he’d explain himself when he returns to NYC to see Sam in hopes of reconnecting. Nope. Could we not have learned that it was the grandma who sent him away? Or maybe he could have confessed not being strong enough to stick around and see the love of his life wither away and die?? SOMETHING! Missed opportunity there.
7) Why is Tara Sam’s doppelgänger? I thought for sure this would come in handy for the hostage exchange at the end. Nope. Wrong again. It’s never used. I thought, maybe Andreas hired her previously because he was in love with Sam since childhood and had used Tara in the past as a guard because of her resemblance to his unrequited love. NOPE. We learn Andreas really hadn’t thought of Sam much over the years (which was EXTREMELY disappointing, in my opinion). So why is this look-alike thing even a thing?
8) What happens to Sam’s apartment? Does she give it up? We’re not told. Is the dead tree ever removed from Andreas’ house. Little details like this made me mentally do the writing to close them out.
9) Does Sam ever give Andreas the damned books!? If she does, we don’t even get to see/read his reaction!! So disappointing. Is there a bonus scene I’m missing where these big gaping holes are finally sewn up? If so, please tell me where.
So, yeh. Lots of issues I need resolved. And then on top of those, Reid takes the liberal rant a step too far with her mention of ICE officers. I get that Sam is a character and as a woman in STEM, in NYC, raised by the parents she was, she’s going to lean left. That said, the ICE jab was current, politically driven, nasty, and personal. I lost some respect for Reid with that. Those officers are people with families to provide for, parents who love them, responsible, wage earning, hard working human beings. Just because they are working a job you find distasteful doesn’t mean they are despicable and morally corrupt. Would Reid be on the front line of citizens who spat on the Vietnam veterans returning from their nightmare 6 months in hell? I know some ICE officers and they are not happy with what they’ve been recently tasked with. They are struggling with mental health issues and PTSD. Quitting is not an option for many. So, please, have some compassion lest you want to be called a complete hypocrite.
All that said, I still love Andreas and Sam together. The reunification was somewhat drawn out, but then all of a sudden they have a few words and are on the mend (albeit slowly). That was a little odd. If I hadn’t already fallen for the characters by then, I wouldn’t be so forgiving of the writing there.
1) Andreas has this strange reaction when learning of the gossip of he and Roman being in a relationship. What was the wince for? I thought we were going to get a hot side-story where Andreas did some “exploring” with Roman. Didn’t have to be major, but some heavy petting would have been hot. lol
2) We’re told Andreas doesn’t get along with Nakita (towards the end of the book as Sam recovers), but never really told why. Is it just because of the time she super fanned him, or because Sam warned him that she publicizes everything she hears? Or did she maybe make a pass at him when they met for coffee?? Did they even MEET for coffee???
3) We NEED MORE ANDREAS. One tiny chapter from the male perspective was not enough. I don’t know why Reid even bothered stating which character’s POV carries each chapter, but the fact she did was frustrating. It never changed and that just made me hope it would! I seriously hope Reid issues another book of this same story but from Andreas’ POV. There might have been a total of two chapters from Andreas throughout the 3-book series now that I think of it. Again, NOT nearly enough. We need some “splaining” please!
4) There’s a point in this book where Sam is explaining to Andreas who has been staying with her to keep her safe from sleepwalking. She says things like “…my friend Diya”, and “my former roommate Nakita…”. WHY!?? Andreas knows these women personally. He’s had dinner, drinks, conversations, etc. with them all. It’s odd. Reid must have written this early on and forgotten to go back and correct? If they’re for the new reader, she shouldn’t bother since nobody can really start fresh at this 3rd book without having read the first two.
5) What happens to the darned shares!? We get some sexy times at the very end (thank GOD, because we readers have waited through 3 full books for Andreas to get his due!) but nothing about the company is wrapped up.
6) Another HUGE question that never gets answered is why Grampa Carl left Sam’s grandma right after her cancer diagnosis. I was certain we’d get the backstory and he’d explain himself when he returns to NYC to see Sam in hopes of reconnecting. Nope. Could we not have learned that it was the grandma who sent him away? Or maybe he could have confessed not being strong enough to stick around and see the love of his life wither away and die?? SOMETHING! Missed opportunity there.
7) Why is Tara Sam’s doppelgänger? I thought for sure this would come in handy for the hostage exchange at the end. Nope. Wrong again. It’s never used. I thought, maybe Andreas hired her previously because he was in love with Sam since childhood and had used Tara in the past as a guard because of her resemblance to his unrequited love. NOPE. We learn Andreas really hadn’t thought of Sam much over the years (which was EXTREMELY disappointing, in my opinion). So why is this look-alike thing even a thing?
8) What happens to Sam’s apartment? Does she give it up? We’re not told. Is the dead tree ever removed from Andreas’ house. Little details like this made me mentally do the writing to close them out.
9) Does Sam ever give Andreas the damned books!? If she does, we don’t even get to see/read his reaction!! So disappointing. Is there a bonus scene I’m missing where these big gaping holes are finally sewn up? If so, please tell me where.
So, yeh. Lots of issues I need resolved. And then on top of those, Reid takes the liberal rant a step too far with her mention of ICE officers. I get that Sam is a character and as a woman in STEM, in NYC, raised by the parents she was, she’s going to lean left. That said, the ICE jab was current, politically driven, nasty, and personal. I lost some respect for Reid with that. Those officers are people with families to provide for, parents who love them, responsible, wage earning, hard working human beings. Just because they are working a job you find distasteful doesn’t mean they are despicable and morally corrupt. Would Reid be on the front line of citizens who spat on the Vietnam veterans returning from their nightmare 6 months in hell? I know some ICE officers and they are not happy with what they’ve been recently tasked with. They are struggling with mental health issues and PTSD. Quitting is not an option for many. So, please, have some compassion lest you want to be called a complete hypocrite.
All that said, I still love Andreas and Sam together. The reunification was somewhat drawn out, but then all of a sudden they have a few words and are on the mend (albeit slowly). That was a little odd. If I hadn’t already fallen for the characters by then, I wouldn’t be so forgiving of the writing there.
This entire review has been hidden because of spoilers.
November 11, 2025
I’m very happy that while Ukrainian journalist Viktoria Roshina’s body was returned home missing organs and showing clear evidence of torture by russia, Western authors are still comfortable enough to add moscow or random russian characters to their books. Because, you know, #notallrussians and a culture built on blood and imperialism is just so cool, right? Besides scientists from any other countries are non-existent, why bother.
Anyway, I didn’t like the final installment of this series. It felt okay-ish, but I was really expecting something else. The relationship between the main characters felt a bit clinical and unrealistic, I couldn’t feel any connection to the pacing and development of their relationship after the cliffhanger in book 2.
We also met the cheaters from previous books in the series, and I was actually happy about the Kaitlyn and Martin (and little Joey) scenes. However, Abraham being described as “the sexiest man alive on planet Earth” every single time he appears really pissed me off.
I’m really glad that Sam got her own trilogy, I just wish we didn’t get those super-genius nepo babies trope, like we did in EoC and LoP.
November 8, 2025
Andreas & Samantha ❤️
🧬PhD student Samantha receives a thick invite in the mail to her own wedding, and she’s more than surprised. The groom is Andreas, the boy who she adored as a child, until everything turned sour.
🧬When Andreas suggests marriage to find a way to circumvent his father’s inheritance wishes, she knows she can’t do it. But an adult adoption could work. Coupled with a fake engagement that will put his evil brothers off the scent may just work.
✏️I am at the point where I have read everything Penny Reid has written, and if she writes it, I am guaranteed to love it. This story is a serial in three parts. The cliffhangers are working hard; its so exciting to see how things will work out for the brilliant chess grand master and the lovely scientist who’s captivated his heart for so many years.
Read on Kindle
My rating 5/5 - ⭐️ ⭐️ ⭐️ ⭐️ ⭐️
Connect with me: http://www.instagram.com/read.athon2021
🧬PhD student Samantha receives a thick invite in the mail to her own wedding, and she’s more than surprised. The groom is Andreas, the boy who she adored as a child, until everything turned sour.
🧬When Andreas suggests marriage to find a way to circumvent his father’s inheritance wishes, she knows she can’t do it. But an adult adoption could work. Coupled with a fake engagement that will put his evil brothers off the scent may just work.
✏️I am at the point where I have read everything Penny Reid has written, and if she writes it, I am guaranteed to love it. This story is a serial in three parts. The cliffhangers are working hard; its so exciting to see how things will work out for the brilliant chess grand master and the lovely scientist who’s captivated his heart for so many years.
Read on Kindle
My rating 5/5 - ⭐️ ⭐️ ⭐️ ⭐️ ⭐️
Connect with me: http://www.instagram.com/read.athon2021
November 8, 2025
Penny Reid does grad student romance better than Ali Hazelwood
It's not a competition, they're both great, but Penny Reid's relationships tend to involve less suffering for the heroine, and more legitimate female friends. Anyways, SPOILERS FOLLOW. I especially love the full circle Kaitlyn friendship, that was delightfully done. I really appreciate that Sam doesn't stand for a power imbalance in her private relationships, and especially Reid's treatment of Sam's complex feelings about the abuser in her department. Meanwhile, GOD, Andreas' progression from untouchable rich chess master to sweats and bluntness is just crack, stick that directly into my VEINS.
Love you Ms. Reid, please do more of these 3-midsize-book installments! So satisfying!!
It's not a competition, they're both great, but Penny Reid's relationships tend to involve less suffering for the heroine, and more legitimate female friends. Anyways, SPOILERS FOLLOW. I especially love the full circle Kaitlyn friendship, that was delightfully done. I really appreciate that Sam doesn't stand for a power imbalance in her private relationships, and especially Reid's treatment of Sam's complex feelings about the abuser in her department. Meanwhile, GOD, Andreas' progression from untouchable rich chess master to sweats and bluntness is just crack, stick that directly into my VEINS.
Love you Ms. Reid, please do more of these 3-midsize-book installments! So satisfying!!
November 11, 2025
I hate that this is the end!
I loved this trilogy and the ending did not disappoint!
The characters, the backstory, the mystery and intrigue I didn’t see coming, The beautiful resolution! Loved it all! Penny Reid did it again!
I loved this trilogy and the ending did not disappoint!
The characters, the backstory, the mystery and intrigue I didn’t see coming, The beautiful resolution! Loved it all! Penny Reid did it again!
November 28, 2025
3 stars
I was fully frustrated in this one. I still didn't understand Andreas and his justifications, Sam was a bit stubborn and overall i felt like the story was just dragging from there. The drama with her bff was a drama on drama and didn't really ad to the story IMO. When they finally get together it felt flat. Overall a bit disappointed by this series, more than 650 pages and while there's certainly potential i didn't loved it as much as i hoped. It's still Penny Reid, it's smart interesting, little tidbid of interesting informations, a very good writing that keep you reading but the love story frustrated me, the intringue was good but filled with holes though ^^
I was fully frustrated in this one. I still didn't understand Andreas and his justifications, Sam was a bit stubborn and overall i felt like the story was just dragging from there. The drama with her bff was a drama on drama and didn't really ad to the story IMO. When they finally get together it felt flat. Overall a bit disappointed by this series, more than 650 pages and while there's certainly potential i didn't loved it as much as i hoped. It's still Penny Reid, it's smart interesting, little tidbid of interesting informations, a very good writing that keep you reading but the love story frustrated me, the intringue was good but filled with holes though ^^
November 16, 2025
Really Good…
Penny Reid’s books are always so good, that said, I look up the meaning of more words in one of her books than I do in all the others I read…this is not a bad thing…
Penny Reid’s books are always so good, that said, I look up the meaning of more words in one of her books than I do in all the others I read…this is not a bad thing…
December 9, 2025
2.75
I'm going to put some general notes under the first book in the trilogy
I'm going to put some general notes under the first book in the trilogy
December 20, 2025
Enh. I never say that about a Penny Reid book, but...
There is it. I wonder if it would have been better if I could have read all three back to back?
There is it. I wonder if it would have been better if I could have read all three back to back?
November 9, 2025
Definitely my favorite of the series. But of these 3 set STEM series, this was also my favorite. I just really liked Sam and Andreas. I also loved the extra drama in this book with Kaitlyn and Joey. Plus Sam certainly put Andreas thru his paces to earn back her trust and forgiveness.
November 15, 2025
Hilarious and Thought Provoking
Ms Reid concludes this delightful trilogy with wit and emotional intelligence. The plot is filled with intriguing elements. The banter is fun and the heat is blazing. I highly recommend this book and series.
Ms Reid concludes this delightful trilogy with wit and emotional intelligence. The plot is filled with intriguing elements. The banter is fun and the heat is blazing. I highly recommend this book and series.
January 14, 2026
this is insanely dragged out seriously what was the author thinking. Half of the book is about why doesn't he apologize like whats this nonsense. 0 star useless book written just for $$
January 21, 2026
Penny Reid writes such mesmerizing, incredibly smart, lovely romances
This will be my full review of the Fundamentals of Biology trilogy. Wow, what a wild ride. I did not see where this story would take me, and going blind was so much fun. In these books, we follow Samantha and Andreas, two estranged childhood best friends who meet again in their late 20s when partnering up is needed to carry out an inheritance scheme. Samantha is a PhD candidate struggling in every aspect of her life, as someone in academia only can, and Andreas is pretty much the best chess player on Earth with a Machiavellian aura. Totally my type of chaotic remix in a romance!
The plan Andreas comes up with is quite complex and convoluted. I believe finding out about it while reading will be a better reading experience, so I'm not going to go into too much detail about this plot point. What is important here is that fake dating is needed to carry out the scheme, so as a lover of this trope, it was a delight to read my fav author's super unique interpretation of it.
What stole the show for me, though, was Andreas and Samantha's interpersonal dynamics. They both have different traumas from their upbringing that make them very wary of starting any emotional connection at first. They were best friends once, and that kinship made it seamless for them to continue that friendship even after years of no contact. The thing is, now, as adults, there is a deeper attraction that is enhanced by the fact that they need to act as a couple. They do not know how to handle these new feelings because, as previously mentioned, they are emotionally stunted lovely idiots, and seeing both of them, in their own ways, fumble up was damn cute.
The scheme also added a bit of a mystery to the plot, but what it did from the very beginning was show the incredibly masterful mind that is Andreas. As a chess player, he lives his life using the same philosophy as in his tournaments: always being 20 steps ahead, and understanding what move will benefit him the most. This makes him incredibly detail-oriented and translates positively in some aspects, but it was also the downfall of their blooming relationship. He needed to learn how to trust Samantha, how to be a partner, and share his next move so they can make decisions together. Not an easy feat after many years living solo, surrounded by a toxic as hell family, and having a job that requires the exact opposite mindset. He does get there, and oh boy, when this guy opens up his heart fully and loves with no pretenses, it made me so giddy.
Sam was no flawless character either, and this is how I like 'em tbh. Her trust issues spring up from a different root, but fundamentally make her as wary as Andreas to open her heart fully, which at some points leads her to not be as fully transparent as she should. She is afraid of losing things that are important to her, so she never attaches to anything. This is why their relationship first starts as something physical, and this development was indeed very hot. When things looked like they were going somewhere deeper, Andreas' aforementioned scheming derails this epically, BUT some of Sam's actions do play a role in their separation. In the 3rd book, we get some grovelling from Andreas (very much needed), and Sam (needed as well but not as much), and big personal growth from both of them. I must emphasize here that I'm the biggest fan of how Penny handled the conflict resolution!!
First of all, I loved how it took a long while for them to get back to a place of trust and openness. What caused the conflict was pretty hurtful, and forgiving easily and fast would NOT have worked at all. It wasn't your typical chapter at the end of a book where the character in the wrong makes a big love declaration, and everything is instantly resolved. Nope, the cadence was slow and extremely coherent. Not only did the slowness make sense, but also the fact that loving each other is not the problem; the trust that was broken is the biggest bump in the road for their relationship. I loved how Penny explored this concept, how a couple can move on from a betrayal and open up their hearts again, because, sadly, sometimes loving someone is simply not enough to make a relationship work, and a lot of work must be involved in nourishing a loving bond back to health.
I 100% recommend these books. Penny Reid is a phenomenal author. I'm so in awe every time I finish one of her novels, and I'm so happy she is publishing again after her hiatus. As a disclaimer, I need to say that I will probably re-read this trilogy at some point in the future because I read book 1 & 2 right after finishing The Long Game and I was in the BIGGEST book hangover (plus in the middle of my Heated Rivalry TV show fever dream) so I may not have given these the attention they do so deserve.
This will be my full review of the Fundamentals of Biology trilogy. Wow, what a wild ride. I did not see where this story would take me, and going blind was so much fun. In these books, we follow Samantha and Andreas, two estranged childhood best friends who meet again in their late 20s when partnering up is needed to carry out an inheritance scheme. Samantha is a PhD candidate struggling in every aspect of her life, as someone in academia only can, and Andreas is pretty much the best chess player on Earth with a Machiavellian aura. Totally my type of chaotic remix in a romance!
The plan Andreas comes up with is quite complex and convoluted. I believe finding out about it while reading will be a better reading experience, so I'm not going to go into too much detail about this plot point. What is important here is that fake dating is needed to carry out the scheme, so as a lover of this trope, it was a delight to read my fav author's super unique interpretation of it.
What stole the show for me, though, was Andreas and Samantha's interpersonal dynamics. They both have different traumas from their upbringing that make them very wary of starting any emotional connection at first. They were best friends once, and that kinship made it seamless for them to continue that friendship even after years of no contact. The thing is, now, as adults, there is a deeper attraction that is enhanced by the fact that they need to act as a couple. They do not know how to handle these new feelings because, as previously mentioned, they are emotionally stunted lovely idiots, and seeing both of them, in their own ways, fumble up was damn cute.
The scheme also added a bit of a mystery to the plot, but what it did from the very beginning was show the incredibly masterful mind that is Andreas. As a chess player, he lives his life using the same philosophy as in his tournaments: always being 20 steps ahead, and understanding what move will benefit him the most. This makes him incredibly detail-oriented and translates positively in some aspects, but it was also the downfall of their blooming relationship. He needed to learn how to trust Samantha, how to be a partner, and share his next move so they can make decisions together. Not an easy feat after many years living solo, surrounded by a toxic as hell family, and having a job that requires the exact opposite mindset. He does get there, and oh boy, when this guy opens up his heart fully and loves with no pretenses, it made me so giddy.
Sam was no flawless character either, and this is how I like 'em tbh. Her trust issues spring up from a different root, but fundamentally make her as wary as Andreas to open her heart fully, which at some points leads her to not be as fully transparent as she should. She is afraid of losing things that are important to her, so she never attaches to anything. This is why their relationship first starts as something physical, and this development was indeed very hot. When things looked like they were going somewhere deeper, Andreas' aforementioned scheming derails this epically, BUT some of Sam's actions do play a role in their separation. In the 3rd book, we get some grovelling from Andreas (very much needed), and Sam (needed as well but not as much), and big personal growth from both of them. I must emphasize here that I'm the biggest fan of how Penny handled the conflict resolution!!
First of all, I loved how it took a long while for them to get back to a place of trust and openness. What caused the conflict was pretty hurtful, and forgiving easily and fast would NOT have worked at all. It wasn't your typical chapter at the end of a book where the character in the wrong makes a big love declaration, and everything is instantly resolved. Nope, the cadence was slow and extremely coherent. Not only did the slowness make sense, but also the fact that loving each other is not the problem; the trust that was broken is the biggest bump in the road for their relationship. I loved how Penny explored this concept, how a couple can move on from a betrayal and open up their hearts again, because, sadly, sometimes loving someone is simply not enough to make a relationship work, and a lot of work must be involved in nourishing a loving bond back to health.
I 100% recommend these books. Penny Reid is a phenomenal author. I'm so in awe every time I finish one of her novels, and I'm so happy she is publishing again after her hiatus. As a disclaimer, I need to say that I will probably re-read this trilogy at some point in the future because I read book 1 & 2 right after finishing The Long Game and I was in the BIGGEST book hangover (plus in the middle of my Heated Rivalry TV show fever dream) so I may not have given these the attention they do so deserve.
January 3, 2026
I wrote one review for the series and am posting it for all three. Don't hate me, I'm being efficient, and in the wise words of the Doctor... no spoilers.
✦Series: Hypothesis, 7-9 • ♟️Fundamentals of Biology 1-3♟️
MF romcom with a heavy dose of suspense. The return of the Hypothesis series is smart, twisty, funny, and completely bingeable. I devoured the trilogy in two days.
1️⃣ Inheritance
Andreas approaches Samantha with an unconventional way to take back her birthright and restore her late parents’ reputations.
2️⃣ Reproduction
Their fake engagement doesn’t feel so fake once they move in together to make it look real; they’ve been crushing on each other since they were kids. It doesn’t help that Sam keeps sleepwalking into Andreas’ bed. Hello, one bed!
Aside: the twist at the end of this one made me want to scream. Well done, Penny! I did not see that coming.
3️⃣ Evolution
Sam will take back what should always have been hers with or without Andreas, but Andreas has no intention of letting her go.
Here’s where it goes wild with drama and suspense. It’s thrilling, and the way Penny weaves the subplots together is straight-up wizardry.
✦POV: Single, first-person
The books are told in Sam’s POV with Andreas as the last chapter in books 1+2. This was a brilliant idea. Understanding his struggles in the moment cranked the drama and kept me obsessively reading.
Sam is a STEM PhD candidate. She’s strong, funny, clever, and relatable. I loved reading her thoughts and how she navigated what the story threw at her.
Andreas is a young, billionaire, chess grandmaster who earned fame because he’s undefeated and wields stoicism like a weapon. His character arc was so unexpected! His hopeless devotion to Sam is tender and swoony.
✦Spice: Open door, explicit
It’s a slooow burn, but it is worth every page to get there. The tension is achingly delicious. 😮💨🫠
♡ Eloquent, funny, clever- Penny’s books lock me in, I’m hooked every time. The stories her mind conjures are a gift! Enjoy with confidence. 👏
⚠️ Please check trigger warnings!
✨ Enjoyed thanks to Toronto Public Library and Libby.
⭐️⭐️⭐️⭐️½ rounded up!
→ Connect with me on Instagram!
✦Series: Hypothesis, 7-9 • ♟️Fundamentals of Biology 1-3♟️
MF romcom with a heavy dose of suspense. The return of the Hypothesis series is smart, twisty, funny, and completely bingeable. I devoured the trilogy in two days.
1️⃣ Inheritance
Andreas approaches Samantha with an unconventional way to take back her birthright and restore her late parents’ reputations.
2️⃣ Reproduction
Their fake engagement doesn’t feel so fake once they move in together to make it look real; they’ve been crushing on each other since they were kids. It doesn’t help that Sam keeps sleepwalking into Andreas’ bed. Hello, one bed!
Aside: the twist at the end of this one made me want to scream. Well done, Penny! I did not see that coming.
3️⃣ Evolution
Sam will take back what should always have been hers with or without Andreas, but Andreas has no intention of letting her go.
Here’s where it goes wild with drama and suspense. It’s thrilling, and the way Penny weaves the subplots together is straight-up wizardry.
✦POV: Single, first-person
The books are told in Sam’s POV with Andreas as the last chapter in books 1+2. This was a brilliant idea. Understanding his struggles in the moment cranked the drama and kept me obsessively reading.
Sam is a STEM PhD candidate. She’s strong, funny, clever, and relatable. I loved reading her thoughts and how she navigated what the story threw at her.
Andreas is a young, billionaire, chess grandmaster who earned fame because he’s undefeated and wields stoicism like a weapon. His character arc was so unexpected! His hopeless devotion to Sam is tender and swoony.
✦Spice: Open door, explicit
It’s a slooow burn, but it is worth every page to get there. The tension is achingly delicious. 😮💨🫠
♡ Eloquent, funny, clever- Penny’s books lock me in, I’m hooked every time. The stories her mind conjures are a gift! Enjoy with confidence. 👏
⚠️ Please check trigger warnings!
✨ Enjoyed thanks to Toronto Public Library and Libby.
⭐️⭐️⭐️⭐️½ rounded up!
→ Connect with me on Instagram!
January 12, 2026
I wrote one review for the series and am posting it for all three. Don't hate me, I'm being efficient, and in the wise words of the Doctor... no spoilers.
✦Series: Hypothesis, 7-9 • ♟️Fundamentals of Biology 1-3♟️
MF romcom with a heavy dose of suspense. The return of the Hypothesis series is smart, twisty, funny, and completely bingeable. I devoured the trilogy in two days.
1️⃣ Inheritance
Andreas approaches Samantha with an unconventional way to take back her birthright and restore her late parents’ reputations.
2️⃣ Reproduction
Their fake engagement doesn’t feel so fake once they move in together to make it look real; they’ve been crushing on each other since they were kids. It doesn’t help that Sam keeps sleepwalking into Andreas’ bed. Hello, one bed!
Aside: the twist at the end of this one made me want to scream. Well done, Penny! I did not see that coming.
3️⃣ Evolution
Sam will take back what should always have been hers with or without Andreas, but Andreas has no intention of letting her go.
Here’s where it goes wild with drama and suspense. It’s thrilling, and the way Penny weaves the subplots together is straight-up wizardry.
✦POV: Single, first-person
The books are told in Sam’s POV with Andreas as the last chapter in books 1+2. This was a brilliant idea. Understanding his struggles in the moment cranked the drama and kept me obsessively reading.
Sam is a STEM PhD candidate. She’s strong, funny, clever, and relatable. I loved reading her thoughts and how she navigated what the story threw at her.
Andreas is a young, billionaire, chess grandmaster who earned fame because he’s undefeated and wields stoicism like a weapon. His character arc was so unexpected! His hopeless devotion to Sam is tender and swoony.
✦Spice: Open door, explicit
It’s a slooow burn, but it is worth every page to get there. The tension is achingly delicious. 😮💨🫠
♡ Eloquent, funny, clever- Penny’s books lock me in, I’m hooked every time. The stories her mind conjures are a gift! Enjoy with confidence. 👏
⚠️ Please check trigger warnings!
✨ Enjoyed thanks to Toronto Public Library and Libby.
⭐️⭐️⭐️⭐️½ rounded up!
→ Connect with me on Instagram!
✦Series: Hypothesis, 7-9 • ♟️Fundamentals of Biology 1-3♟️
MF romcom with a heavy dose of suspense. The return of the Hypothesis series is smart, twisty, funny, and completely bingeable. I devoured the trilogy in two days.
1️⃣ Inheritance
Andreas approaches Samantha with an unconventional way to take back her birthright and restore her late parents’ reputations.
2️⃣ Reproduction
Their fake engagement doesn’t feel so fake once they move in together to make it look real; they’ve been crushing on each other since they were kids. It doesn’t help that Sam keeps sleepwalking into Andreas’ bed. Hello, one bed!
Aside: the twist at the end of this one made me want to scream. Well done, Penny! I did not see that coming.
3️⃣ Evolution
Sam will take back what should always have been hers with or without Andreas, but Andreas has no intention of letting her go.
Here’s where it goes wild with drama and suspense. It’s thrilling, and the way Penny weaves the subplots together is straight-up wizardry.
✦POV: Single, first-person
The books are told in Sam’s POV with Andreas as the last chapter in books 1+2. This was a brilliant idea. Understanding his struggles in the moment cranked the drama and kept me obsessively reading.
Sam is a STEM PhD candidate. She’s strong, funny, clever, and relatable. I loved reading her thoughts and how she navigated what the story threw at her.
Andreas is a young, billionaire, chess grandmaster who earned fame because he’s undefeated and wields stoicism like a weapon. His character arc was so unexpected! His hopeless devotion to Sam is tender and swoony.
✦Spice: Open door, explicit
It’s a slooow burn, but it is worth every page to get there. The tension is achingly delicious. 😮💨🫠
♡ Eloquent, funny, clever- Penny’s books lock me in, I’m hooked every time. The stories her mind conjures are a gift! Enjoy with confidence. 👏
⚠️ Please check trigger warnings!
✨ Enjoyed thanks to Toronto Public Library and Libby.
⭐️⭐️⭐️⭐️½ rounded up!
→ Connect with me on Instagram!
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