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 issues 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. Also it was a little short compared to the other books. Overall, I still enjoyed the story and look forward to the rest of the series.

Dan is still working on a plan to stop Victoria Stahl, but for now he and Sam must jump through time to the eve of the Battle of Thermopylae. Spartans and allies face a massive Persian army. A glitch in time could alter the future, if they cannot find and correct it.

Very well written and well narrated novel (I listened to the audiobook). Good characters in this time travel novel. We will see a different perspective on the battle and political intrigue. Action packed and well,paced.

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.

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.

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

Andrew Varga does it again! After book three, I was questioning if this series is my favorite series. After book four, I can confirm, yes, this is my favorite series.

This series continues to perfectly balance a modern-day plot and a time-jumping plot, and weave them together perfectly. In book four, Dan and Sam jump back to the battle of Thermopylae. Dan and Sam reference the movie 300, which is probably where most of our brains go when we think about the Spartans versus the Persians.

This was one of the best plot lines in the past, and that’s saying a lot because everyone has been amazing. Dan inserts him self into the battle as a Spartan warrior. Dan even beats a Spartan in a fist fight to show he is a warrior, which cements the fact that Dan is a superhero.

This is the bloodiest and most violent time jump yet, and these jumps are really affecting Dan. The modern-day plot with Victor also had some great reveals, which has me on the edge of my seat waiting for book 5.

The love triangle from the last book is still present, and I remain team Sam. I love Sam’s development, and given some of the reveals in this book, I think we are just getting started with her.

I’ll say it again, A Jump in Time is my favorite series. You are doing yourself a disservice by not reading these books. What are you waiting for!?

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.

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.

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 ) 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.

Interesting concept and fast paced book about travelling into the past to keep history more or less the same so our existing reality don't just collapse. I didn't read the first three books but I got enough context from the story itself to more or less follow what they're doing and the motives of the main characters. Because it has time travel element and "unexpected mistakes" happened while they are in the past, when I listened to the audiobook, I get an overall "I'm following a doctor who story" vibe, although there's less of the assurance someone can come in and save the day.

I don't know if I enjoyed the writing exactly, on the other hand. A lot of times, I kind of feel like there's more telling than showing? The characters keeps telling me why things matters and it gets very repetitive. Maybe because I didn't read the first three books, I'm not feeling the tension and urgency for a lot of the story where the main characters are clearly bothered or tortured about what they might face. I'm also not a huge fan of the love triangle and some of those dialogues in those the chapters that has more focus centered on those plot point felt flat and even made the characters a bit unlikable for a minute there. Logically I know I should have more empathy for Dan because he's still a teenager, but I didn't really feel that way through the writing. I can see the appeal of the way things are presented and maybe they just don't work very well for me.

The narrator also did a good job for the audiobook. I might try the other books in this series and see if I'll like them better when I have more time.

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.

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.