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The hunt for the Sovereign has begun

Echo and River have blurred the line between Dead Born and Green Born, revealing the ultimate secret. They’ve discovered there’s a way to save humanity. The Sovereign is the one who carries true immunity against the deadly superbees.

And now they must find her.

As the first Dead Born to have Immunity, Echo is the logical conclusion. Except countless have died in the search for the Sovereign. Because the one way to be sure is to be stung by a queen bee.

Only the true Sovereign will survive.

283 pages, Kindle Edition

Published January 20, 2023

185 people are currently reading
281 people want to read

About the author

Tamar Sloan

141 books431 followers
Tamar really struggled writing this bio, in part because it’s in third person, but mostly because she hasn’t decided whether she’s primarily a psychologist who loves writing, or a writer with a lifelong fascination with psychology.

She must have been someone pretty awesome in a previous life (past life regression indicated a Care Bear), because she gets to do both. Beginning her career as a youth worker, then a secondary school teacher, before becoming a school psychologist, Tamar helps children and teens to live and thrive despite life’s hurdles like loss, relationship difficulties, mental health issues, and trauma.

As lover of reading, inspired by books that sparked beautiful movies in her head, Tamar loves to write young adult romance. To be honest, it was probably inevitable that her knowledge and love of literature would translate into writing emotion driven stories of finding life and love beyond our comfort zones. You can find out more about Tamar’s books at www.tamarsloan.com

A lifetime consumer of knowledge, Tamar holds degrees in Applied Science, Education and Psychology. When not reading, writing or working with teens, Tamar can be found with her husband and two children enjoying country life on their small slice of the Australian bush.
The driving force for all of Tamar’s writing is sharing and connecting. In truth, connecting with others is why she writes. She loves to hear from readers and fellow writers. Find her on all the usual social media channels or her website.

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5 stars
212 (37%)
4 stars
215 (38%)
3 stars
105 (18%)
2 stars
26 (4%)
1 star
6 (1%)
Displaying 1 - 30 of 55 reviews
Profile Image for Michelle.
117 reviews10 followers
June 14, 2024
Loving this series, Echo and River draw you in and captivate you, can't wait to read the next book
Profile Image for readingwithmissbec.
151 reviews33 followers
June 16, 2024
OH MY GOODNESS .. I need more!

The plot thickens!

So many thoughts..
this book had me on the edge of my seat.. needing to know, who, what, when, where, how?

I will be continuing my obsession with this series!
Profile Image for Jessica.
1,154 reviews29 followers
March 3, 2023
Echo and River have discovered there's a way to save mankind. The Sovereign is the only one with true immunity against the superbees, but they have to find the right person. Echo seems to be the logical answer, since she's the first from the Dead Zone who's immune. To be certain they have to test Echo - by letting her get stung by a queen bee. If they're wrong she won't survive the sting...

The first book ended in a cruel cliffhanger and this book starts exactly were the former ended, so you have to read Harvest Day to understand what's it all about. Since the cliffhanger was quite adrenaline-stuffed it's action from the beginning! Everyone also seem to have secrets that are revealed one after the other, and I've been surprised several times. Other times things feel very logical and therefore predictable, but I think there's a nice mix. I do feel like the pacing was a bit uneven and there were some repetitions.

This book also ends with a cliffhanger, although of a different kind. I'm happy that the next book is releasing in a couple of weeks!

* I received an ARC from the authors and I'm giving my honest review. *
Profile Image for Christine Cazeneuve.
1,462 reviews40 followers
January 23, 2023
Much better

I enjoyed this second book in the series more than the first. Exciting storyline and wonderful characters (gotta love Makk!). You will cheer, laugh, smirk, get angry, scared, confused and frustrated along with our main characters. Can't wait for the next book coming out in April! Also it has to be mentioned that the names of all the characters are truly unique!
82 reviews5 followers
January 22, 2023
Second book in the series. The first one ended on a cliffhanger and then this book was released a month early so I was super excited.

However, it lacked the excitement of the first one and seemed very sophomoric. Overarching plot points seem to make less sense in this book and it's starting to seem a little hacky.
This entire review has been hidden because of spoilers.
Profile Image for Cassie .
27 reviews
June 23, 2024
After learning the truth about Harvest Day, Echo and River escape from the Green Zone. Only to find more horrors buried beneath the Dead Zone. A secret facility with a deadly guardian.
Echo, River, Chase and Flora risk their lives in their search for the Sovereign and permanent immunity. Can they find the answers they seek before time runs out? And what other secrets will come to light?

Hive Mind is the second book in The Sovereign Code series. I’ve really become invested in the outcome of this series and will be starting book three Queen Hunt very soon.
Profile Image for Toast.
98 reviews2 followers
January 12, 2024
The second book of the Sovereign Code series is better than the first. The action begins immediately, picking up where the first book left off. So much happens in a short span (less than a week), that I found myself in the edge of my seat waiting to see what would happen next. River and Echos relationship blooms despite the trouble and danger they face at every turn. The friendships formed and lost keep pace with the severity of the plot. However there are enough comedic and sweet moments that the entire story doesn’t feel bogged down with serious issues.
Profile Image for Sam.
2,550 reviews41 followers
January 23, 2023
A really great second part to this new & exciting dystopian adventure! I really like the ideas & overall feel of this really scary world. Brilliant storyline mixed with interesting characters make this a very enjoyable read! You never know where the plot will go! A really great experience & I am really looking forward to the next part!
Profile Image for Pandora.
422 reviews134 followers
June 12, 2024
This series has me gripped! The dystopian world I didn't know I needed.
I have so many questions and yet did get a lot of answers in this book. I'm looking forward to diving into book three next.
Profile Image for Laura C.
536 reviews5 followers
July 11, 2024
The second book in The Sovereign Code series.

I enjoyed it but it wasn’t as good as Harvest Day. I loved the twists but it had more romance than the first book which I didn’t like. Overall a good plot.

Looking forward to reading the next book.
Profile Image for ems_booknook.
445 reviews19 followers
June 11, 2024
Holy moly, so much going on in this one! Lots and lots of questions rising but also a lot of stuff coming together.

One thing I’ve noticed about these authors - never assume you know 🤣
Profile Image for Corrine.
5 reviews2 followers
July 20, 2023
Hive Mind is the second book in The Sovereign Code series, and picks up where we left off at the end of book one.

This was another excellent book in the series, I found it to be a quick read however there was a lot of development through out. We were able to see more of our main characters relationships with each other, more back stories we didn’t previously get from the first book all without slowing down the current events.

This book also ended on a cliffhanger and I’m really looking forward to the rest of the series and how everything is going to work out.

*A Thank you goes to Heidi Catherine and Tamar Sloan for providing this ARC in return for an honest review!*
2,996 reviews43 followers
April 24, 2023
This is book two of The Sovereign Code and the main characters are River and Echo, one Green Born brought up in the luxury of the Green Zone where food is plentiful, and the other being Dead Born brought up in a life where every day is a fight for survival in the Dead Zone, where nothing can grow. They have discovered some of the secrets that the Green Zone and in particular, that River’s father Oren, has been hiding. Echo was the very first Dead Born to have immunity from bee stings in nearly two decades, whilst River’s own twin sister Flora, was found to be Vulnerable and forced to leave the Green Zone through the black door, to a world she has never known in the Dead Zone. She would be a target for those that live there, who have a hatred for those in the Green Zone and their lives of plenty, whilst their own families die of starvation and have nothing. Oren has placed Echo in the LaB and desperately wants a sample of her blood, but won’t say why. River has been placed back in Eden, where Clover works, and has also been told to mentor Echo and show her around, but to really keep an eye on her and check out her loyalties to the Green Zone! He misses his twin sister Flora and can’t believe how cold his father is about her absence. All he seems to care about is life going on as normal.

In reality, Oren has been testing people to find out who might be the Sovereign, the one who is immune to the sting of a queen bee and would be the answer to immunity for all, from the deadly super bees. It would be the answer to saving humanity once and for all, so long as the same mistakes aren’t made, but Oren has no desire to give immunity to any of the Dead Zone, only limiting it to those he trusts in his small elite group. Echo and River may have started out kind of hating each other, but there is an attraction between them, as well as a sense of trust. They are shocked at the secrets they find and what his father has been doing in secret all these years. Lies will be told to them, some to hurt them, some to protect them. Nothing they do is going to be safe, as they break down the wall of secrets in the search for the Sovereign and the possibility it could be Echo herself who could save them all. The only problem is that there is only one way to test if someone is the Sovereign and that is to have them stung by a queen bee, something that is deadly whether you are Immune or Vulnerable! They also find out personally, exactly how Adrenacure is made and where its main ingredient comes from, which is a scary time! Chase is back and with a bit part to play in this one, as does Flora to some extent. Young Makk is an interesting character and I hope to see more of him in the following stories. Clover is an annoying and deluded character, who believes herself in love with River and that grates as she clearly can’t think for herself or even see what is in front of her! Loads of danger and excitement in this one, as the action ramps up even more. I can’t wait to see what on Earth is going to happen next, as it left us on a bit of a cliff hanger! I received an ARC copy of this book from BookSprout and I have freely given my own opinion of the book above.
Profile Image for Katheyer.
1,557 reviews25 followers
January 22, 2023
“Hive Mind” takes on exactly where “Harvest” left on, with Echo and River trapped in the Hive after Oren’s betrayal. In the course of the story the real workings behind the societal split in Green/Dead zone and the truth about Immunity/Vulnerability become clear, as Echo and River unite forces with Chase and Flora to try to overcome the system, and find a true source of Immunity.

Tamar Sloan & Heidi Catherine, authors of the wide-acclaimed “Thaw Verse”, have with the “Sovereign Code” created a brand-new dystopian world, that is a great contender for an ex-quo place in the best dystopian verse of this decade after just two books in the series. Even if my heart belongs (and will always!!) to the “Thaw Verse”, I’m already making place for Echo, River, Flora, and the bees 😉.

Sloan & Catherine’s wonderful dystopian world, foreign yet familiar, beautiful, and terrifying captivates the reader at first read. Their fluid and nuanced writing conveys a powerful message, whose actuality plainly apparent. The extraordinary thoroughly built world is populated by well developed and multifaceted characters, credible and relatable at all times. YA fast-paced story, that provides action non-stop, an intelligent plot, and very satisfactory developments, a real page-turner, a great adventure that leaves a lasting impression without disregarding the level of pure entertainment every good story should provide. Beware though of some ‘side-effects’ as sleep-hours lost (should you start the book in the evening) and a brand-new appreciation for honey 😉

Sloan & Catherine dystopia effortlessly surpassed YA classical works as “The Hunger Games” and “Divergent”, even surpasses them offering not just very carefully crafted worlds, the right balance between dystopia and social critique, with a constant questioning of the values and drawbacks of the system that allows the reader to understand the strengths and flaws and find unsettling similarities to our own society and values.
Profile Image for Reads_Must .
959 reviews13 followers
January 21, 2023
Hive Mind
The Sovereign Code #2
Fantasy, Sci/Fi, Dystopian
Tamar Sloan, Heidi Catherine
⭐️⭐️⭐️⭐️⭐️

I love a good dystopian book and yet again Tamar Sloan and Heidi Catherine have written a great one. They're both on my favourite authors list and everytime I see another book is planned or I'm sent an ARC, I get so excited!

The pacing was so good, I finished reading in about 3 hours because I just couldn't put it down!

The characters were just as developed as they were in the first book and I still loved them all, even the side characters. They all have their own voices and personalities. Makk was such a cute character and I loved his energy. I'm intrigued about Nola, I think she definitely knew more than she let on and that she's left some more clues behind for River and Echo to find.

The world building was great. I liked how new places were discovered and explored which led to secrets being revealed. There are things that tie into the previous book and help make sense of different plot twists, although I did predict a couple of them new ones but that didn't stop me from enjoying them.

This book is a great addition to the series and I can't wait to read the next one!

*A huge thank yout o Heidi Catherine and Tamar Sloan for providing this ARC in return for an honest review*
Profile Image for alishasbooknook.
195 reviews2 followers
October 19, 2024
I absolutely loved the second book of The Sovereign Code! From the very start I was drawn into an intricate world that the authors created. The exploration of connection and self-discovery is not just a theme but a journey that will resonate with you.

The characters are incredibly well developed and relatable. Each character has their own unique struggles and triumphs, which makes it easy to empathize with them. I found myself invested in their journeys and rooting for their successes and feeling their pain. Again, I love Echo and now also love River. Those are tied in first place for me. I absolutely loved seeing the character development of certain characters.

The writing style is engaging and beautifully crafted. The authors have a knack for weaving together vivid imagery and emotional writing, making it easy to lose track of time while reading. The narrative flows smoothly, with each chapter leaving me eager to turn the page. I was completely hooked, I couldn’t read fast enough, I needed to know what would happen and I had multiple physical reactions, ranging from shock, happiness, anger and so much more.

I’m super excited to start the third book, I already love this series so much and I highly recommend it so far, it’s an incredible dystopian series.
Profile Image for Michelle (easy.vesey.reads).
249 reviews2 followers
September 28, 2024
I stayed up late and woke up early just to be able to finish this one, that’s how good it was! Hive Mind was action packed and had me on the edge of my seat the entire time!

I was holding out hope that Echo would not be the Sovereign because that would make the story too predictable. My bet was on Navy, but looks like I was wrong on that front too. Maybe Flora is the only logical choice or it’s a character we haven’t even met yet!

Also, I’m still worried that someone in the group is going to betray them all. I can’t see it being River but I wouldn’t be surprised if Chase gave them up to redeem himself now that the Razers don’t trust him anymore.

Once again, the plot twist at the end had me screaming! But also it makes so much sense because we couldn’t just have that one thing resolved so quickly when there’s still 3 books left in the series! There’s still soooo much unresolved and we are no where near finding out the truth about anything. I can’t wait to see where this story goes next!
1,221 reviews15 followers
June 16, 2025
Action-Packed, Dystopian Romance
To save bees from extinction, humans turned them into deadly superbees—and created a dystopia. Now there’s the Green Zone, where the privileged live in comfort, and the Dead Zone, where people struggle and die young. River is Green Born. Echo is Dead Born. Their story begins in Book 1, and this is definitely a series that should be read in order.
Together, Echo and River are searching for a cure—a cure that may lie in the blood of the Sovereign. Could Echo be the one? Only the true Sovereign can survive a sting from a queen bee. Getting it wrong could mean death.
This story is action-packed, full of twists, danger, and heart. Echo and River must face those who hoard power in the Green Zone—people who would rather protect their own wealth than save humanity. One of those people is River’s father. How do you cope when your sire is part of the corruption you're fighting?
I recommend this to readers who enjoy dystopian stories with clean romance, relentless adventure, and characters who risk everything for a better world.
Profile Image for Mrs LIR Linda.
389 reviews13 followers
January 16, 2023
This is the second book of what looks to be a 5 part saga.
The love story hinted at in Hive is beautifully developed, and the parallel love story of Flora and Chase comes to the fore.
The harvesting of adrenaline is depicted in a very gruelling manner, as is the hunt for the female who carries the 'sovereign' strain. However, to find out if that girl is the carrier, she must be stung by a Queenbee..... and some are forced into this situation.
The story follows the factions of the green zone and dead zone and how some want to fight, and some want to find a solution for all.... and some want to be the omnipotent cruel leaders.
Again, a cliffhanger of an end, but hope for the 4 main protagonists..... maybe finding a presumed dead person..... also a clue maybe why is the chair important....
I look forward to the next episode. Heidi and Tamar really know how to keep a reader enthralled.
I was given a free ARC by the authors, and I leave this review voluntarily. Thank you.
Profile Image for Rebecca Bean.
57 reviews3 followers
November 30, 2025
Pretty good book, considering the same reservations I had with the first one.

I still have a few things that bug me. It seems unclear how long this Green Zone/ Dead Zone thing has been set up. No one seems to be alive that remembers anything else, but there doesn't seem to be enough people, etc for it to have existed for generations. I'm also skeptical about 17-yr-old Flora being capable of drawing spinal fluid and all the other stuff she does. Especially since the Green Zone has pretty much everything handled via technology, so I don't she would ever have had a chance to learn how to do those things manually.

There's sex at one point, but the actual deed is only alluded to. I was wondering for a bit, because the kissing and such beforehand was getting pretty descriptive, but more like maybe the author(s) read romance novels and the vibe seeped into their books.

Love Makk. Low-key can't stand Chase. He makes the worst decisions.
960 reviews
March 2, 2023
First, I must say that I love Tamar’s books! And the colaboration with Heidi for the Thaw series result in some great books!
So, only this and I was excited for this serie - on the start of the first book. But soon, their intriguing crafted world and complex characters hooked me. The end of the first book left me with a lot of questions and a damn cliffhanger, after such terrifying scene.
This book was the same - a thrilling story, with a lots of twists, some trully unexpected.
And the same wonderful main characters, with some new ones.
In this book, some answers were provided, but more are to come.
And can’t waitforthe next one! And the next. And the next…. Becouse I hope that this universe will develop and expand, and new stories will be written.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.
Profile Image for McKayla.
416 reviews3 followers
August 21, 2023
Super original

This series is basically the Hunger Games, Divergent, and Maze Runner had a baby. It follows the journey of two teens from very different sections of the world, and the bees are deadly to humankind. One teen is safe, and the other has to work at surviving through the day. River and Echo form a reluctant partnership when faced with the differences between their worlds, and the reality that immunity could very well just be a social construct. I read the first two books of the five book series and as much as I enjoyed it, it wasn’t hitting “the spot” for me. I found the plot didn’t correspond well with the character development which rubbed me the wrong way. Some of it felt too rushed and as a result it was hard to enjoy the milestones of the slow burn. I would still recommend the series as it is super intriguing, and so original.
Profile Image for Avo_in_bookland (Narelle) .
121 reviews4 followers
November 17, 2024
Hive Mind is Book 2 in the Sovereign Series. Continues straight on from Book one but the plot thickens. Echo and River have blurred the lines between the Green and Dead Zone revealing the ultimate Secret.

By the edge of our seats we go on the journey along with Echo and River as they discover that there is a way to save humanity. The Sovereign is the only truely Immune against the bees. And Echo seems the only Logical choice.

This will be a dangerous journey to test Echo to find out if she is the true Sovereign. Countless others have died while trying. To test Echo she must be stung by the Queen Bee. If they are wrong she won’t Survive the sting.

Honestly not wanting to put this book down, I feel like I’m truely part of the adventure. We learn more about Flora and Chase. And have a range of quirky characters along the way. Definitely moving straight into Book 3 Queen Hunt.
Profile Image for Becky Doyle.
72 reviews3 followers
June 15, 2024
Hive mind is the second in the Harvest Day series. Where the last book left you on an intense cliffhanger I did find myself somewhat disappointed in the slower pace of the second book, but that aside I still enjoyed the next instillation of the book. The book focuses much less on the relationships of our main characters and more on uncovering the terrible secrets of the GreenZone , and the search for the sovereign who will provide all with immunity. Tensions run high as the GreenZone and DeadZone cross paths again and again in the battle for equality, food, and immunity. The book does leave you wanting to read the next in the series to continue on. I do wish maybe we got a little more of the thrill and passion of the first book, but I am keen to continue the series.
Profile Image for Jennifer Krider.
136 reviews
October 1, 2023
I want to like this book, it is well written, but there are a few plot lines that I am having a hard time getting through.
1) if they are putting something in the water to make them immune- why do they need the sovereign? Or the medicine?
2) why kill or forgotten the younger generation? Why only allow 2 people to be immune?
3) why mechanical bees??? That took me out. The whole time I am wondering who built them and why? And the main characters just accept it.
4) why aren't they trying to go after the medicine in the water to give to the deadborns?
These items took me out of this world and made it easy to put down

This entire review has been hidden because of spoilers.
Profile Image for DeeDeeWReads.
1,157 reviews16 followers
March 3, 2023
The search continues for the one that holds the key to immunity for all. Who will it be? IS it Eden? If it is, how are they going to find out when her and River are a little 'stuck' at the moment.

This one brings some revelations and also I STILL don't have a theory I've had since book 1 proven or NOT. UGH.... I won't share here, but if you know what I'm thinking, I think we'll get our answer in book 3.

There's loss, rebellion, friends become more, and family ties get tested slightly.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.
Profile Image for Jessica Fuller.
410 reviews79 followers
December 28, 2023
OH MY GOD!

That was absolutely incredible from start to finish.
The shocks, the twists, the turns, the emotions… I’m still reeling. Also, that ending! Omg these authors know how to make you need to grab the next book immediately. This series is one of those series where you are still thinking about it when you’re not reading it. Where you connect with the characters and feel like they are your friends. I am so grateful I have the whole set so I can start reading the next one. I could not put this book down which is evident in the fact that it’s now past 12:30am haha
Profile Image for It’s Jess.
146 reviews2 followers
April 6, 2025
Ohhhhh this was such a heartbreaking, and horrifying way to begin book 2.
I was so anxious for both Echo & River.
And the tense way it began, continued throughout the entire book!
Exhilarating and fast paced, I was on the edge of my seat. It never slowed down!
As with the first book, I tried the Audio but could not stand the voice and the imitations and accents the one female narrator made were hard to listen to.
So I continued on reading it physically.
I also do not like Chase.. never have.. he gives me the “ick”.
Profile Image for Annie Kosar.
361 reviews2 followers
January 26, 2023
SECRETS REVEALED & TONS OF ADVENTURE & DYSTOPIAN HEART STOPPING ROMANCE!!:-)

REALLY LOVING THIS SERIES!!!:-). The secrets in this one are revealed in just the right way and keep the reader guessing all the way through!!:-). I could NOT stop turning the pages and I feel like my heart stopped a few times JK:-). The romance was deep and sensual in a powerfully psychic way!!!:-). Cannot WAIT for the next one in this series and ANYTHING from these authors!!!:-). LOVED IT!!:-)
Profile Image for Shannon.
128 reviews
April 4, 2025
They think they have found the one immune to a queens sting. The only problem is now they need to figure out how to make everyone else immune as well. Once administered they find out they were wrong about who was the true immune. As their worlds come crashing down Flora tells her brother the real reason she went to the dead zone was so she could find their mother and that's when he finds out his mother is still alive
This entire review has been hidden because of spoilers.
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