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A Jump in Time #4
The Spartan Sacrifice
Whoever Controls the Past Writes the Future
With Victor Stahl’s plot to rule the world on an unstoppable path in the present, seventeen-year-old time jumper Dan Renfrew and his partner Sam realize that their only hope of putting an end to Victor’s scheme is to jump into the past again. They arrive in Greece in the year 480 BCE just before the legendary Battle of Thermopylae, where a heavily outnumbered force of Spartan warriors and their Greek allies bravely try to prevent Greece from being overrun by the invading Persian army. But when a horrible accident happens in the past, Dan and Sam discover that Victor’s plot is the least of their worries.
With Victor Stahl’s plot to rule the world on an unstoppable path in the present, seventeen-year-old time jumper Dan Renfrew and his partner Sam realize that their only hope of putting an end to Victor’s scheme is to jump into the past again. They arrive in Greece in the year 480 BCE just before the legendary Battle of Thermopylae, where a heavily outnumbered force of Spartan warriors and their Greek allies bravely try to prevent Greece from being overrun by the invading Persian army. But when a horrible accident happens in the past, Dan and Sam discover that Victor’s plot is the least of their worries.
304 pages, Hardcover
Published August 5, 2025
1 person is currently reading
19 people want to read
About the author
Andrew Varga
7 books92 followersI am a YA historical fiction author who takes great pains to ensure historical accuracy in my books, while still ensuring that I tell a great story. Although I enjoy reading and writing about all history, I have a particular fondness for European history from Greco-Roman times until the crusades.
I hope you enjoy my stories.
I hope you enjoy my stories.
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Displaying 1 - 30 of 38 reviews
July 2, 2025
Thank you to Netgalley, the publisher, and the author for providing a free audio arc in exchange for an honest review.
This series has been quite enjoyable, and I feel like if I read them when I was a teen, it would have been a favorite series. This time, we travel back in time to Leonidas and his army, facing off against the Persians and Dan and Sam getting pulled into the battle to help. This time though, things really don't go as planned, leading to Dan possibly being trapped in time. We also get more story with the villain Victor Stahl, but find out that there is more involved in this sinister time traveling society than what we thought.
The plot was great, and action scenes were good. The only issue I had was the drama between Dan, Sam, and Jenna. Obviously, these are still teens/young adults, and we know how relationships at that age can be. It was just cringey at times and annoying. Overall, I still enjoyed the story and look forward to the rest of the series.
This series has been quite enjoyable, and I feel like if I read them when I was a teen, it would have been a favorite series. This time, we travel back in time to Leonidas and his army, facing off against the Persians and Dan and Sam getting pulled into the battle to help. This time though, things really don't go as planned, leading to Dan possibly being trapped in time. We also get more story with the villain Victor Stahl, but find out that there is more involved in this sinister time traveling society than what we thought.
The plot was great, and action scenes were good. The only issue I had was the drama between Dan, Sam, and Jenna. Obviously, these are still teens/young adults, and we know how relationships at that age can be. It was just cringey at times and annoying. Overall, I still enjoyed the story and look forward to the rest of the series.
January 12, 2026
Thank you to NetGalley and the publisher for providing an advance copy in exchange for an honest review.
Andrew Varga’s novel The Spartan Sacrifice is a rich compelling historical fiction novel for young adults. I was drawn to the historical scenery of ancient Sparta and the accuracy of historical content that is mentioned for readers. Being a history major this for me was a big plus!
Additional to the historical content, the story of Dan and Sam and their time jumping to save the world from Victor Stahl was thrilling and an adventurous read.
I hope the author writes more of these books for Young adults!
Andrew Varga’s novel The Spartan Sacrifice is a rich compelling historical fiction novel for young adults. I was drawn to the historical scenery of ancient Sparta and the accuracy of historical content that is mentioned for readers. Being a history major this for me was a big plus!
Additional to the historical content, the story of Dan and Sam and their time jumping to save the world from Victor Stahl was thrilling and an adventurous read.
I hope the author writes more of these books for Young adults!
April 7, 2025
Dan's latest jump takes him all the way back to ancient Greece, days before the famous Battle of Thermopylae.
With the stakes higher than ever and Dan questioning the lengths he can go, he and Sam are deeper and deeper entangled in Victor Stahl's net.
As the story progresses, some missing puzzle pieces of the overarching plot are falling in place, but said plot doesn't appear particularly well thought and has several huge holes in its reasoning.
This can be overlooked though since the series has a light adventure vibe from the start - what cannot be ignored for me 4 books in, is the cringe, cheesy teen love triangle plotlines. The less said about this, the better. It does a huge disservice to the series.
Thank you NetGalley for the ARC!
With the stakes higher than ever and Dan questioning the lengths he can go, he and Sam are deeper and deeper entangled in Victor Stahl's net.
As the story progresses, some missing puzzle pieces of the overarching plot are falling in place, but said plot doesn't appear particularly well thought and has several huge holes in its reasoning.
This can be overlooked though since the series has a light adventure vibe from the start - what cannot be ignored for me 4 books in, is the cringe, cheesy teen love triangle plotlines. The less said about this, the better. It does a huge disservice to the series.
Thank you NetGalley for the ARC!
November 25, 2025
My first Jump in Time novel and it was easy to enter this world and enjoy it. Girls are more of a helper role in this series, unfortunately. Still found it fun and with a great, fast plot.
January 15, 2026
Loved it such a clever series hope him and Sam have another adventure
April 9, 2025
Another brilliant instalment by Andrew Varga.
This one got me emotional very early on because it took me back to an ancient history class that I loved when I was 11 years old. Just like Dan becomes giddy after realising he is seeing some of his heroes, I was almost choked up.
It was a good book with some interesting twists: some unexpected, while others strongly foreshadowed (especially the big stuff at the end).
I love the writing style. It is friendly and accessible, keeping me entertained, helping me visualise what is happening, with a good mix of descriptions and dialogue. The suspense is provided in a perfect amount for my taste.
I am really curious how Dan will navigate his way out of the hole he dug himself into. I can see a few possible events, and I cannot wait to read the fifth book.
The sense of mystery is perpetuated. While some questions are answered, more arise. The characters are fairly believable, neither one-dimensional, nor too complex to take away from the interesting plot.
It was fascinating to learn more about Victor's evil plan. Listening to people who believe in it can be very polarising. It makes me reflect on how people in the real world start to have extreme views. This, combined with some of Dan's choices, can really question the readers' ethics and morals.
There is also a level of complexity brought by the fact that the bad guys want to fix the time stream, while also making small changes (addressed by the plot to be of "little consequence") as well as trying to take huge action in the present. I wonder if they fear a chrononaut to visit from their future to fix what I can only describe as the glitch they are setting up. But maybe there is no glitch cause Dan will stop them anyway.
The time travel element is interesting. It is a tool for an interesting story. I advise readers again to not become obsessed about time travel being written "the right way". There is no right way because, as far as we know, time travel is not possible. The only right way of writing about it is to set it up in a way that stimulates readers' imagination. And mine is stimulated. Having said that, the approach used in this series treats time both as a thing that can be revisited, but also as a linear concept with events being visitable only once. If the glitch isn't fixed when it should, the chrononauts cannot try again by jumping back in time repeatedly.
Happy reading!
This one got me emotional very early on because it took me back to an ancient history class that I loved when I was 11 years old. Just like Dan becomes giddy after realising he is seeing some of his heroes, I was almost choked up.
It was a good book with some interesting twists: some unexpected, while others strongly foreshadowed (especially the big stuff at the end).
I love the writing style. It is friendly and accessible, keeping me entertained, helping me visualise what is happening, with a good mix of descriptions and dialogue. The suspense is provided in a perfect amount for my taste.
I am really curious how Dan will navigate his way out of the hole he dug himself into. I can see a few possible events, and I cannot wait to read the fifth book.
The sense of mystery is perpetuated. While some questions are answered, more arise. The characters are fairly believable, neither one-dimensional, nor too complex to take away from the interesting plot.
It was fascinating to learn more about Victor's evil plan. Listening to people who believe in it can be very polarising. It makes me reflect on how people in the real world start to have extreme views. This, combined with some of Dan's choices, can really question the readers' ethics and morals.
There is also a level of complexity brought by the fact that the bad guys want to fix the time stream, while also making small changes (addressed by the plot to be of "little consequence") as well as trying to take huge action in the present. I wonder if they fear a chrononaut to visit from their future to fix what I can only describe as the glitch they are setting up. But maybe there is no glitch cause Dan will stop them anyway.
The time travel element is interesting. It is a tool for an interesting story. I advise readers again to not become obsessed about time travel being written "the right way". There is no right way because, as far as we know, time travel is not possible. The only right way of writing about it is to set it up in a way that stimulates readers' imagination. And mine is stimulated. Having said that, the approach used in this series treats time both as a thing that can be revisited, but also as a linear concept with events being visitable only once. If the glitch isn't fixed when it should, the chrononauts cannot try again by jumping back in time repeatedly.
Happy reading!
July 29, 2025
I really enjoyed this book. I’ve always liked middle grade stories, even if I’m no longer the target audience. This one gave me strong Percy Jackson vibes, it was fun, fast-paced, and easy to follow. Even though the focus is mainly on the Battle of Thermopylae, it still managed to feel light-hearted and funny at times.
The author did an amazing job bringing history to life. I could picture the action and the characters like I was right there on the battlefield. That’s impressive, especially considering how hard it was to visualize ancient military strategies back when I learned about them in school. I really admire the author’s vivid imagination and the clear amount of research that went into this book.
Credit also goes to the narrator, who made the story even more engaging.
I definitely recommend this book if you enjoy Greek mythology, action, or just a great adventure.
Thank you to NetGalley for this audiobook. This is my honest review in return.
The author did an amazing job bringing history to life. I could picture the action and the characters like I was right there on the battlefield. That’s impressive, especially considering how hard it was to visualize ancient military strategies back when I learned about them in school. I really admire the author’s vivid imagination and the clear amount of research that went into this book.
Credit also goes to the narrator, who made the story even more engaging.
I definitely recommend this book if you enjoy Greek mythology, action, or just a great adventure.
Thank you to NetGalley for this audiobook. This is my honest review in return.
July 23, 2025
I've been waiting a long time for this, and now Dan and Sam's Time Jumps are finally continuing :-)
I've been following their adventures since book 1 and am looking forward to the sequels every year.
About the plot: There are actually two plots here that are quite cleverly interwoven. The main plot that connects all the books in the series is the secret society of "Time Jumpers," whose members are equipped with devices that allow them to travel through time. But not just for the fun of it; rather, it's the other way around: whenever there's a "glitch"—some kind of unwanted slip-up—in the flow of time, the devices call the Time Jumpers, and they hop right there and have to set history straight so that everything runs smoothly again. The time travelers never know in advance where they'll end up, and therefore spend their lives training for all eventualities.... Yes, and one of the jumpers, Victor Stahl, mentioned in the blurb, has recognized his chances for world domination and is the dark force that must be fought. The fight against Victor runs through all the books, and in each book, the evil one's perfidious plan is revealed a few steps further...
The second plot, of course, is always the current time travel adventure of Dan and Sam, the two more or less involuntary jumpers. This time, they land in ancient Greece in the year 480 BC, and the Battle of Thermopylae is imminent. In case that doesn't mean anything to anyone: that was the legendary battle of Sparta's "300," the Spartan superheroes who defied the Persian superpower.... Sam didn't know it either, and Dan, who certainly had received plenty of history lessons from his father, also mainly remembers the epic Hollywood film of the same name, which gave him various fanboy moments.....now it's time to figure out which "glitch" needs to be fixed, and soon Dan finds himself in the middle of the central battle....and that's a far different story "in real life" than in the cinema seat....
And of course, we have a tender romance in there – we remember, Samantha and Daniel have grown closer in the last few books, but Dan now has a steady girlfriend at home, Jenna, and has to decide what he actually wants.
So, let's get to my reading experience: it was once again extremely cool. Super exciting, tons of action, lots of emotion, grippingly written. Considering that this is actually a young adult book (Sam, Jenna, and Dan are 17 years old), I'm absolutely thrilled. The author grabs you from page one, and you're in the flow.
And you can also tell that the author is a historian; the books are all historically very accurate. Very precise. Everything here is absolutely spot on, and I think that's great. I completely buy into everything he says; it's really funny, actually.
The characters develop further from book to book, and I think you can definitely read this book on its own—you're given enough background information on everything—but of course, it's more exciting to jump in from the beginning. So, read all four books! I very much recommend reading them!
Many thanks to Netgalley and the publisher for the brilliant review copy! I enjoyed it :-)
I've been following their adventures since book 1 and am looking forward to the sequels every year.
About the plot: There are actually two plots here that are quite cleverly interwoven. The main plot that connects all the books in the series is the secret society of "Time Jumpers," whose members are equipped with devices that allow them to travel through time. But not just for the fun of it; rather, it's the other way around: whenever there's a "glitch"—some kind of unwanted slip-up—in the flow of time, the devices call the Time Jumpers, and they hop right there and have to set history straight so that everything runs smoothly again. The time travelers never know in advance where they'll end up, and therefore spend their lives training for all eventualities.... Yes, and one of the jumpers, Victor Stahl, mentioned in the blurb, has recognized his chances for world domination and is the dark force that must be fought. The fight against Victor runs through all the books, and in each book, the evil one's perfidious plan is revealed a few steps further...
The second plot, of course, is always the current time travel adventure of Dan and Sam, the two more or less involuntary jumpers. This time, they land in ancient Greece in the year 480 BC, and the Battle of Thermopylae is imminent. In case that doesn't mean anything to anyone: that was the legendary battle of Sparta's "300," the Spartan superheroes who defied the Persian superpower.... Sam didn't know it either, and Dan, who certainly had received plenty of history lessons from his father, also mainly remembers the epic Hollywood film of the same name, which gave him various fanboy moments.....now it's time to figure out which "glitch" needs to be fixed, and soon Dan finds himself in the middle of the central battle....and that's a far different story "in real life" than in the cinema seat....
And of course, we have a tender romance in there – we remember, Samantha and Daniel have grown closer in the last few books, but Dan now has a steady girlfriend at home, Jenna, and has to decide what he actually wants.
So, let's get to my reading experience: it was once again extremely cool. Super exciting, tons of action, lots of emotion, grippingly written. Considering that this is actually a young adult book (Sam, Jenna, and Dan are 17 years old), I'm absolutely thrilled. The author grabs you from page one, and you're in the flow.
And you can also tell that the author is a historian; the books are all historically very accurate. Very precise. Everything here is absolutely spot on, and I think that's great. I completely buy into everything he says; it's really funny, actually.
The characters develop further from book to book, and I think you can definitely read this book on its own—you're given enough background information on everything—but of course, it's more exciting to jump in from the beginning. So, read all four books! I very much recommend reading them!
Many thanks to Netgalley and the publisher for the brilliant review copy! I enjoyed it :-)
July 6, 2025
Title: The Spartan Sacrifice
Series: A Jump in Time Book #4
Author: Andrew Varga
Format: 🎧
Narrator: Mark Sanderlin
Publisher: Imbrifex Books
Genre: Sci Fi, Time Travel, Historical Fiction
Pub Date: August 5, 2025
My Rating: 4.5 Stars
Pages: 304
Although this is my first read in this series and I do realize it would be best to read an earlier one
In this story Victor Stahl’s is the bad guy and has survived many years as many hate him. He has a strong base, money and power.
Victor wants to rule the world on an unstoppable path.
Victor likes seventeen-year-old Dan Renfrew as he knows Dan is a time jumper – something Victor isn’t but wants.
Dan doesn’t want to help Victor - as he had his entire family killed. Dan and his partner Sam realize that their only hope of putting an end to Victor’s scheme is to jump into the past again.
I am not the target audience for this story but I do love time travel. In this story they are called ‘Time Jumpers’.
This story turned out to be a WOW read for me!!! I am now looking forward to next in this series.
I read a lot of fiction so when a story genre states ‘Historical Fiction”
Although there is a section at the end entitled ‘Historical Notes’, I did look it up.
~480 BCE Battle of Greece
Greece faced the Second Persian Invasion, a major conflict in the - Persian Wars. The key
events included the Battle of Thermopylae, where a small Greek force, including 300 Spartans,
bravely held off a much larger Persian army, and the Battle of Salamis, a decisive naval
victory for the Greeks against the Persian fleet. These events ultimately led to the Persian
retreat and marked a turning point in the war. ~
Yes there was a Battle in Greece in 480 BCE (Before Common Era) and many of the soldiers
listed were recorded as being there!
Want to thank NetGalley and Imbrifex Books for granted me this audiobook.
Publishing Release Date scheduled for August 5, 2025.
Series: A Jump in Time Book #4
Author: Andrew Varga
Format: 🎧
Narrator: Mark Sanderlin
Publisher: Imbrifex Books
Genre: Sci Fi, Time Travel, Historical Fiction
Pub Date: August 5, 2025
My Rating: 4.5 Stars
Pages: 304
Although this is my first read in this series and I do realize it would be best to read an earlier one
In this story Victor Stahl’s is the bad guy and has survived many years as many hate him. He has a strong base, money and power.
Victor wants to rule the world on an unstoppable path.
Victor likes seventeen-year-old Dan Renfrew as he knows Dan is a time jumper – something Victor isn’t but wants.
Dan doesn’t want to help Victor - as he had his entire family killed. Dan and his partner Sam realize that their only hope of putting an end to Victor’s scheme is to jump into the past again.
I am not the target audience for this story but I do love time travel. In this story they are called ‘Time Jumpers’.
This story turned out to be a WOW read for me!!! I am now looking forward to next in this series.
I read a lot of fiction so when a story genre states ‘Historical Fiction”
Although there is a section at the end entitled ‘Historical Notes’, I did look it up.
~480 BCE Battle of Greece
Greece faced the Second Persian Invasion, a major conflict in the - Persian Wars. The key
events included the Battle of Thermopylae, where a small Greek force, including 300 Spartans,
bravely held off a much larger Persian army, and the Battle of Salamis, a decisive naval
victory for the Greeks against the Persian fleet. These events ultimately led to the Persian
retreat and marked a turning point in the war. ~
Yes there was a Battle in Greece in 480 BCE (Before Common Era) and many of the soldiers
listed were recorded as being there!
Want to thank NetGalley and Imbrifex Books for granted me this audiobook.
Publishing Release Date scheduled for August 5, 2025.
September 1, 2025
As a now seasoned Time Jumper, Dan Renfrew is no stranger to the dangers of the past. In his present, the dastardly Victor Stahl is attempting to secure global domination by altering the past and killing anyone who stands in his way. Though Stahl’s influence is vast, however, a small band of Time Jumpers is determined to do whatever it takes to stop Stahl before lasting damage can be done. When a glitch sends Dan and his best friend Sam back to Ancient Greece, the stakes get higher, and the two must summon all their knowledge and courage to resolve the problem in the time stream in order to preserve their lives in the past, the present, and the future. This fourth in the Jump in Time series takes Dan and Sam on an adventure into Ancient Greece during the famed Battle of Thermopylae. Historical details are juxtaposed against contemporary sensibilities to effectively imagine what it might be like for readers to step into the past, themselves. Though there are reminders of previous adventures embedded within the narrative of this book, readers should be familiar with the first three stories before moving into this one to ensure they have enough foundational knowledge to understand this novel. Action forward and fast-paced, this story is well suited to young adult readers with an interest in both history and adventure. Occasional strong language and light romantic moments appear within the narrative, but the overall design and delivery of the series as a whole can be enjoyed by a wide range of young adult readers. Told in the first person from Dan’s perspective, the novel gives readers a clear idea of the rationale behind all of Dan’s actions. And as the story progresses, readers will be inspired not only to root for Dan’s survival, but also for a clearer understanding of the relationship Dan and Sam share. Engaging, action-packed, and filled with satisfying historical details, this is a good addition both to its series in particular and to library collections for young adult readers in general.
August 12, 2025
When I first picked this book up I had no idea it was part of a series. I was intrigued by the time travel premise, and that the main character would be traveling back in time to ancient Greece, during the battle of the 300. I will say that for being part of a series, and several books in at that, I didn’t have much trouble picking up what was going on in the story. The events that carry over from one story to the next are explained pretty well for those that may be jumping in late like I was. However, I definitely wouldn’t consider these to be stand alones. I will be going back and starting at the beginning to read through the other books in the series as I enjoyed this one. The characters are great, I did have a few questions about some of the characters, but I think that is mostly due to me missing the first three books of the series. The main character lives alone as their parents have passed away, but they seem to also be in high school still, which seemed odd. But like I said that could be addressed in the earlier books. For the events of this story, I thought this book was great. The time travel has a really interesting premise. The idea is that sometimes glitches happen where a historical event will take some type of change leading to things not working out the way that it is supposed to. I really liked this idea, it seemed like a unique take on a time travel story. I found the twists that happened to be really great, and they weren’t things that I anticipated, which I always love. The characters are likeable, and I found myself invested In how they came out of situations in the book. I listened to the audiobook, and I really enjoyed the narrator. The way they brought the story to life definitely kept me invested in the story. I would defini8tloey recommend this one, but start with book 1!
March 9, 2025
5 Stars! I really love this series! This is book 4 in ‘A Jump in Time’ series & it could be a standalone but would be better off being read in order. It’s been a minute since I read book 3, but luckily the author gives info that jog the memory. If you enjoyed the movie ‘300’, this is a book to read. I feel smarter having read this book and it didn’t bore the heck out of me like most history books do. A lot is fictional but it also has many historical facts that are interesting to read about. Did you know Spartan boys were sent away to basically a military school at the age of 7? Entertaining, wonderful main characters, funny at parts, tragic at times, unpredictable, and informative. All in all, totally worth reading, especially for middle and highschoolers but great for adults as well. I usually like romance books but I really enjoy Andrew Varga’s series. He writes so well & everything flows together perfectly. If I had to pick one negative, I’d say I don’t like how the story for Samantha & Dan, the main characters, won’t wrap up until the final book. They have a back & forth relationship and are trying to stop an evil politician and I just can’t wait to read the rest of the series to see how it all gets wrapped up! It’s not really a cliff hanger, which I loathe to my core, so it’s acceptable and I won’t take any stars away. So, I highly recommend this whole series. You’ll really enjoy it and you’ll feel smarter for having read it! It’s a win/win!
*I received this book at no charge & I voluntarily left this review.*
*I received this book at no charge & I voluntarily left this review.*
November 17, 2025
A Jump in Time #4: The Spartan Sacrifice
Andrew Varga
This is fourth book in the A Jump In Time series. I have enjoyed the first 3 and this one did not disappoint.
The premise of the series is a man named Victor Stahl greatest desire is to rule the world; he knows if he controls the past, he can control the future. Our hero is seventeen-year-old Dan Renfrew, and his partner is Sam. If they are going to prevent Victor from succeeding, they must once again jump into the past. This time their jump takes them to Greece in the year 480 BCE. They arrive just before the Battle of Thermopylae. The Spartan warriors led by Leonidas, along with their Greek buddies attempt to stop Greece from being taken over by the Persia. Our heroes have no choice but to assist in the battle. When something goes wrong Dan may be trapped, unable to return to the present.
In book 4 we learn more about Victor and his plan. The relationship between Dan, Sam and Jenna was not well done. It would have been better if that part had been discarded. Dan is still trapped, and we eagerly await book 5 to see if/how he manages to get himself out of the problem. I’ve always enjoyed time travel books, while the focus of this book is middle school students, adults can enjoy it too. My favorite part of this series is factual history; readers can learn history while being entertained.
I received a digital copy of this book from NetGalley in exchange for a fair and unbiased review.
Andrew Varga
This is fourth book in the A Jump In Time series. I have enjoyed the first 3 and this one did not disappoint.
The premise of the series is a man named Victor Stahl greatest desire is to rule the world; he knows if he controls the past, he can control the future. Our hero is seventeen-year-old Dan Renfrew, and his partner is Sam. If they are going to prevent Victor from succeeding, they must once again jump into the past. This time their jump takes them to Greece in the year 480 BCE. They arrive just before the Battle of Thermopylae. The Spartan warriors led by Leonidas, along with their Greek buddies attempt to stop Greece from being taken over by the Persia. Our heroes have no choice but to assist in the battle. When something goes wrong Dan may be trapped, unable to return to the present.
In book 4 we learn more about Victor and his plan. The relationship between Dan, Sam and Jenna was not well done. It would have been better if that part had been discarded. Dan is still trapped, and we eagerly await book 5 to see if/how he manages to get himself out of the problem. I’ve always enjoyed time travel books, while the focus of this book is middle school students, adults can enjoy it too. My favorite part of this series is factual history; readers can learn history while being entertained.
I received a digital copy of this book from NetGalley in exchange for a fair and unbiased review.
July 12, 2025
Interesting! Fun! Historical! Page tuner! Ready for the next book! This book is a fun combination of fantasy and historical fiction. Andrew Varga does a great job of giving us a fun and exciting history lesson. The history delivered in these time jumping books is just awesome.
The action in the book has a perfect pace and it seems like there is always something new going on. This is a great way to get a history lesson The information at the end of the audiobook gives more information about the history of the time. I listened to the audiobook and the narrator did a great job.- Mark Sanderlin. He has narrated all of these audiobooks and it was good to hear his voice doing this one.
The way the story and characters are developed in this book help you experience so many emotions - sadness, humor, suspense, regret, fear, celebration, hope. The main characters are young adults that are easy to relate to. I love the way the characters share what they are thinking and then say something totally different, because what they are feeling is an unacceptable response. You learn so much about them thru their thoughts. They think things that all of us have thought, whether young or old.
The action in the book has a perfect pace and it seems like there is always something new going on. This is a great way to get a history lesson The information at the end of the audiobook gives more information about the history of the time. I listened to the audiobook and the narrator did a great job.- Mark Sanderlin. He has narrated all of these audiobooks and it was good to hear his voice doing this one.
The way the story and characters are developed in this book help you experience so many emotions - sadness, humor, suspense, regret, fear, celebration, hope. The main characters are young adults that are easy to relate to. I love the way the characters share what they are thinking and then say something totally different, because what they are feeling is an unacceptable response. You learn so much about them thru their thoughts. They think things that all of us have thought, whether young or old.
July 8, 2025
This audiobook, narrated by Mark Sanderlin, is a much awaited addition to the Jump in Time Novel series. Sanderlin's narration is appropriately youthful in voicing Dan. Author Andrew Varga this time takes us to ancient Greece, where Sam and Dan must try to ensure that the Battle of Thermopylae ends as it should.
As a woman, Sam isn't able to contribute as much as she'd like to the fight but she's got Dan's back, despite their bickering and awkwardness with one another. Things go horribly wrong in battle and Dan finds himself dressing and acting the part of Leonidas, leader of the Spartans. As all this is unfolding, two other time jumpers, working to help Victor's ambitious plan to become President through making small changes to the past, show up and Sam and Dan have to best them as well. Historically, Leonidas must die during the battle. Does that mean Dan will as well?
This is an exciting read for followers of the series. YA readers, teens, and anyone who likes a good dystopian historical fiction tale will want to read this book.
Note: I listened to an audio advance copy, courtesy of NetGalley.
As a woman, Sam isn't able to contribute as much as she'd like to the fight but she's got Dan's back, despite their bickering and awkwardness with one another. Things go horribly wrong in battle and Dan finds himself dressing and acting the part of Leonidas, leader of the Spartans. As all this is unfolding, two other time jumpers, working to help Victor's ambitious plan to become President through making small changes to the past, show up and Sam and Dan have to best them as well. Historically, Leonidas must die during the battle. Does that mean Dan will as well?
This is an exciting read for followers of the series. YA readers, teens, and anyone who likes a good dystopian historical fiction tale will want to read this book.
Note: I listened to an audio advance copy, courtesy of NetGalley.
July 24, 2025
Many thanks to NetGalley, Imbrifex Books/Imbrifex Audio and the author for the ARC/ALC of this book in exchange for an honest review.
This has to be the first time in this series I felt like, 'Immediately 4 stars.' Not only were the stakes much higher, but also there was significant growth in Dan's personality, perspective, and moral compass.
Dan is getting better at this whole being a 'normal' teenager thing, with school and girlfriend, all while waiting for a major history event that will let him go back in time and do something about Victor's plan of world domination. But when that happens, it (as usual) does not go as planned—this time even more so. Dan and Sam end up in Ancient Greece right when the Spartans and the Greeks are at the cusp of the historical battle of Thermopylae. Not only do they have to fix the time glitch but also follow through with pretty much the only plan they have against Victor.
This one had much more emotional depth, especially with Dan finally going through the 'why me' thoughts. The aftermath of all these events on the relationships between all characters is pretty believable, and the twist, let me tell you, was twisted. The narrator, as always, was convincing and dependable.
This has to be the first time in this series I felt like, 'Immediately 4 stars.' Not only were the stakes much higher, but also there was significant growth in Dan's personality, perspective, and moral compass.
Dan is getting better at this whole being a 'normal' teenager thing, with school and girlfriend, all while waiting for a major history event that will let him go back in time and do something about Victor's plan of world domination. But when that happens, it (as usual) does not go as planned—this time even more so. Dan and Sam end up in Ancient Greece right when the Spartans and the Greeks are at the cusp of the historical battle of Thermopylae. Not only do they have to fix the time glitch but also follow through with pretty much the only plan they have against Victor.
This one had much more emotional depth, especially with Dan finally going through the 'why me' thoughts. The aftermath of all these events on the relationships between all characters is pretty believable, and the twist, let me tell you, was twisted. The narrator, as always, was convincing and dependable.
August 29, 2025
Dan and Sam are at their wits ends trying to find out a way to stop Victors plan to rule the world. If they can’t find a way in the present the next best bet is to jump into the past. When the next jump comes, Dan is thrilled to find himself in 480 BCE at the Battle of Thermopylae. 300 Spartan soldiers and a small force of Greece allies are facing off against the massive Persian army of King Xerxes. But the unthinkable happens and fixing things may not be possible. Suddenly Dan and Sam’s problems are much bigger than Victor.
I am really enjoying this series. I think the author has done a good job keeping things historically accurate and that makes me really happy. Although there were definitely a line pulled from 300. There are some pretty big story answers in this book regarding the overarching present time story line. Also I’ve been curious what happens if the glitch goes wrong and this book answered that. Finding out about Sam’s dad was a bit shocking and I worry about how she will deal but there is still a bit of books left in the series and I can’t wait for the next one.
Rating 3.5 stars
*I received a review copy from NetGalley for my voluntary and honest review
I am really enjoying this series. I think the author has done a good job keeping things historically accurate and that makes me really happy. Although there were definitely a line pulled from 300. There are some pretty big story answers in this book regarding the overarching present time story line. Also I’ve been curious what happens if the glitch goes wrong and this book answered that. Finding out about Sam’s dad was a bit shocking and I worry about how she will deal but there is still a bit of books left in the series and I can’t wait for the next one.
Rating 3.5 stars
*I received a review copy from NetGalley for my voluntary and honest review
April 23, 2025
The 4th novel in a phenomenal YA Sci-Fi/Fantasy series that is one part historical war drama and one part time travel mystery, this book focuses a little less on the relationship between MCs Dan and Sam and a bit more on the other time travellers and their backgrounds. The major historical battle of Thermopylae (Sparta and Greeks vs. Persians) is the highlighted military affair and, like all of the previous books, the storyline is outstanding, realistic, and moving. The attention to detail and the research on Spartan culture and the battle scenes are apparent in nearly every page. The writing style flows quickly and is fast-paced without ever missing a beat. The Spartan chant/poem gave me chills. I love it and if you have enjoyed the other books in the A Jump in Time series, you'll want to read this one too. One of the best series of its kind. I suggest reading the entire series in order for the best experience. Applause for the gorgeous cover art too. Recommended.
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July 31, 2025
I received a digital ARC from the publisher (Imbrifex Books) through Netgalley in exchange for an honest review.
This was a fun continuation in the time jumpers' series. I loved learning more about Sparta, the battle at Thermopylae, and the Persians. The amount of research that went into making the historical setting so vivid and unforgettable is undeniable. There is always that one person who Dan meets in the past who has such an influence on the shape of events, and this one is no exception. I also liked how the plot seems to focus more on the modern day conspiracy vs. resolving time travel glitches now that Dan and Sam are pretty competent time jumpers. I could take or leave most of the recurring side characters, who don't really add much to the story. Hearing more about time jumper lore is always a plus, and this book delivered. I am apprehensive about how a miscommunication/concealing information trope appears to be incoming, but will see how everything ends up playing out. Dan and Sam both had some good growth and I am eager to see when and where they go next.
This was a fun continuation in the time jumpers' series. I loved learning more about Sparta, the battle at Thermopylae, and the Persians. The amount of research that went into making the historical setting so vivid and unforgettable is undeniable. There is always that one person who Dan meets in the past who has such an influence on the shape of events, and this one is no exception. I also liked how the plot seems to focus more on the modern day conspiracy vs. resolving time travel glitches now that Dan and Sam are pretty competent time jumpers. I could take or leave most of the recurring side characters, who don't really add much to the story. Hearing more about time jumper lore is always a plus, and this book delivered. I am apprehensive about how a miscommunication/concealing information trope appears to be incoming, but will see how everything ends up playing out. Dan and Sam both had some good growth and I am eager to see when and where they go next.
July 16, 2025
A modern teen is thrust into the heart of the Battle of Thermopylae in this fast-paced, time-travel adventure. Though part of the Jump in Time series, The Spartan Sacrifice stands well on its own—I never felt lost and now plan to read the earlier books.
I read and listened to this while traveling, and it made the downtime something to look forward to. The story was very good—engaging, vivid, and surprisingly suspenseful. Andrew Varga brings the ancient world to life in a way that’s both creative and grounded in history.
Mark Sanderlin delivers a strong, engaging narration that matches the tone and urgency of the plot. A great listen for fans of historical fiction with a twist.
Thanks to NetGalley and the publisher for providing a copy in exchange for an honest review.
#TheSpartanSacrifice #AndrewVarga #MarkSanderlin #AudiobookReview #HistoricalFiction #NetGalleyReviewer #JumpInTimeSeries
I read and listened to this while traveling, and it made the downtime something to look forward to. The story was very good—engaging, vivid, and surprisingly suspenseful. Andrew Varga brings the ancient world to life in a way that’s both creative and grounded in history.
Mark Sanderlin delivers a strong, engaging narration that matches the tone and urgency of the plot. A great listen for fans of historical fiction with a twist.
Thanks to NetGalley and the publisher for providing a copy in exchange for an honest review.
#TheSpartanSacrifice #AndrewVarga #MarkSanderlin #AudiobookReview #HistoricalFiction #NetGalleyReviewer #JumpInTimeSeries
November 8, 2025
The Spartan Sacrifice is the fourth in a series by Andrew Varga. I've read them all, as has my youngest son, who is now in high school. I think this may be my favorite so far. You do NOT need to read the others first, but it will help you understand the characters' relationships.
Dan continues his time traveling with Sam as his companion. This time, he is truly in the spotlight with Sam more in the background. That's in part because a young girl can not easily blend in with Spartan warriors.
If your child has any interest in ancient history, the Greeks, and warfare, this is a great title to weave it all together.
When you or your child/student reads, make sure to read the extended notes at the end. While the story weaves in historical information, the notes solidify it.
Now I'll be eagerly awaiting book 5 next summer!
Thank you to NetGalley and Imbrifex Books for the advance reader digital copy to review. All opinions are my own.
Dan continues his time traveling with Sam as his companion. This time, he is truly in the spotlight with Sam more in the background. That's in part because a young girl can not easily blend in with Spartan warriors.
If your child has any interest in ancient history, the Greeks, and warfare, this is a great title to weave it all together.
When you or your child/student reads, make sure to read the extended notes at the end. While the story weaves in historical information, the notes solidify it.
Now I'll be eagerly awaiting book 5 next summer!
Thank you to NetGalley and Imbrifex Books for the advance reader digital copy to review. All opinions are my own.
February 9, 2026
The Spartan Sacrifice by Andrew Varga is an exhilarating historical fiction adventure that deftly blends time travel with one of history’s most iconic battles. Varga brings the year 480 BCE vividly to life, immersing readers in the tense moments leading up to the Battle of Thermopylae. His portrayal of Spartan valor, strategy, and the camaraderie between warriors feels authentic and thrilling, making history come alive without ever feeling dry or textbook-like.
The narrative’s time-jumping element adds a compelling layer of suspense. Protagonists Dan Renfrew and Sam are relatable and resourceful, grounding the story’s high-concept premise in human stakes. Varga balances historical accuracy with imaginative storytelling, making the novel appealing both to young adult readers and fans of historical adventure alike. The pacing is brisk, the stakes are high, and the twists ensure that readers remain hooked from start to finish.
The narrative’s time-jumping element adds a compelling layer of suspense. Protagonists Dan Renfrew and Sam are relatable and resourceful, grounding the story’s high-concept premise in human stakes. Varga balances historical accuracy with imaginative storytelling, making the novel appealing both to young adult readers and fans of historical adventure alike. The pacing is brisk, the stakes are high, and the twists ensure that readers remain hooked from start to finish.
March 23, 2025
Learning history and having it brought to life so vividly are my favorite aspects of these books, and The Spartan Sacrifice did not disappoint! I got emotional a few times during inspirational speeches, kind gestures, character deaths, etc. The writing really sucks me into the story.
The romance and Dan's inconsistent intellectual reasoning are my least favorite parts of the books. They're largely realistic depictions, but they make me cringe with either how awkward the romantic bits can be or how implausible some of Dan's deductions or lack thereof can be. I think these may be acceptable to the target demographic (younger readers), as I'm in my 40s so not really who these books are for! I still enjoy the overall premise and especially the history lessons, even though these aren't aimed at me as the audience.
The romance and Dan's inconsistent intellectual reasoning are my least favorite parts of the books. They're largely realistic depictions, but they make me cringe with either how awkward the romantic bits can be or how implausible some of Dan's deductions or lack thereof can be. I think these may be acceptable to the target demographic (younger readers), as I'm in my 40s so not really who these books are for! I still enjoy the overall premise and especially the history lessons, even though these aren't aimed at me as the audience.
September 30, 2025
This is the fourth book in the Jump in time series, I must admit I arrived late to the party and I wasn't able to hear the first two books in this series, needless to say they are not really necessary to understand the story, since most of the answers with the main antagonist are exposed ( in my opinion ) in these two books.
Now I got an AAC through netgalley ( Thanks! ) and as usual the narrator it's really good, I dont love his voice but that's a matter of personal opinion, and he has the perfect voice for an older teenage boy.
The story it's good, not life changing but good, educational and enjoyable, I strongly dislike some of the estereotypical attitudes some of the characters have, but well they are not too bad.
I love the historical notes we can find at the end of the book, and I loved this story, not enough spartans if you ask me but close enough.
Now I got an AAC through netgalley ( Thanks! ) and as usual the narrator it's really good, I dont love his voice but that's a matter of personal opinion, and he has the perfect voice for an older teenage boy.
The story it's good, not life changing but good, educational and enjoyable, I strongly dislike some of the estereotypical attitudes some of the characters have, but well they are not too bad.
I love the historical notes we can find at the end of the book, and I loved this story, not enough spartans if you ask me but close enough.
July 15, 2025
Dan and Sam are back to continue their fight as time travelers who are trying to stop Victor Stahl's plan to have time travelers to take over the world. This jump takes them to Greece just before the legendary Battle of Thermopylae. Since 300 is Dan's favorite movie, he feels more than ready to deal with whatever issue caused the glitch. This time Dan's choice ends up causing a ripple effect across time, and now Dan and Sam are in more danger than usual. Once they manage the glitch, they return to their own time where their mission to destroy Victor's plans takes on a whole new urgency. Secrets are revealed and now Dan feels that he is running out of people to trust. This fourth book in the series did not disappoint. I can't wait for the next adventure.
August 3, 2025
This series just keeps getting better & better. It’s like the young adult version of The Magic Treehouse series where every book features a different historical group. Add in the conspiracy with the “bad guys” and it’s a grand adventure. I’m so glad I came upon this series and I look forwards to each installment. Dan is a great character and handles so much on his own as a young man without parents to guide him. The addition of Jenna & her parents into Dan’s life is so great and makes me glad he has some extra support. Dan’s adventure with the Spartans was fun to read and made me want to re-watch 300. It will be so interesting to see where this story goes.
Thanks to NetGalley, Andrew Varga and Imbrifex Books for a copy of this audiobook.
Thanks to NetGalley, Andrew Varga and Imbrifex Books for a copy of this audiobook.
September 24, 2025
This a further episode in the time traveling adventures of Dan and Sam. This we are transported to Ancient Greece in 480BC to the Battle of Thermopylae. The outnumbered armies of the Spartans and Greeks are preparing for battle against a massive Persian army, when a terrible accident occurs. Dan has to step in to prevent a massive glitch in history. It is far worse than Victor’s diabolical plans for the world. As with the three previous books, I thoroughly enjoyed reading this latest episode. The tension was palpable, sucking me in totally. I especially loved the dramatic revelations contained in the final pages. I have to add I was overjoyed to note the a fifth book is in the works. I’m only sad that this will almost a year from now!
October 3, 2025
Thank you Net Galley for this audio . This is book four in a series that I did not read the first three of yet. Sometimes when you jump in later in a series you find yourself lost or confused and that was not the case for me and this book.
The author explained enough of the characters backstory to keep you informed without spoiling the previous books.
This book focused on Dan, a time jumper , his jump partner Sam and their trip back through time to Thermopylae. I absolutely loved the references to the movie 300 . The description of the battle , the Spartans and King Leonidas were perfectly written. I am going to read the first three books now since I enjoyed this one so much .
The author explained enough of the characters backstory to keep you informed without spoiling the previous books.
This book focused on Dan, a time jumper , his jump partner Sam and their trip back through time to Thermopylae. I absolutely loved the references to the movie 300 . The description of the battle , the Spartans and King Leonidas were perfectly written. I am going to read the first three books now since I enjoyed this one so much .
July 16, 2025
Thank you to NetGalley and the publisher for a copy of this audiobook in exchange for an honest review.
This was a great continuation of this series. I really enjoyed that this was set in Ancient Greece and love where this series is going. I can’t wait to see what awaits Sam and Dan, especially with that plot twist at the end. This series is so great and I really feel like I am traveling back in time when reading these books.
This was a great continuation of this series. I really enjoyed that this was set in Ancient Greece and love where this series is going. I can’t wait to see what awaits Sam and Dan, especially with that plot twist at the end. This series is so great and I really feel like I am traveling back in time when reading these books.
July 23, 2025
Thank you NetGalley for the e-ARC!
This one I did enjoy a whole lot better than the previous one. At first the Sparta, I love ancient Greece and Rome. Secondly the the plot was mainly in the past, what I like the most in these books. I dont want to spoil the book as it is the 4th one, but I would say that maybe we finally will get over with the love triangle.
Cannot wait for the continuation.
4 stars from me
This one I did enjoy a whole lot better than the previous one. At first the Sparta, I love ancient Greece and Rome. Secondly the the plot was mainly in the past, what I like the most in these books. I dont want to spoil the book as it is the 4th one, but I would say that maybe we finally will get over with the love triangle.
Cannot wait for the continuation.
4 stars from me
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