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The 6th Extinction #3
Critical Mass: A Post-Apocalyptic Survival Thriller
On the precipice of annihilation, the fate of humanity hangs in the balance.
With the Earth in ruins from three catastrophic impacts, surviving the fallout was only the beginning. Unleashed from its celestial vector, the Prometheus Pathogen ravages those left behind, revealing how controlling life and death is a trait that will always be a driving force. As science advances, so does the threat of wielding that power.
Caught in the fight to access a potential cure, Kyle risks everything he has left to secure a future for his daughter, but the most lethal obstacles are those he can’t see coming. When lines are blurred, the way out may not always be straightforward.
Dallas has spent a lifetime navigating the unknown, though nothing could prepare her for the role she was to assume at the end of a civilization. Thrust into the chaos with an unlikely team, surviving will come down to her ability to trust and rely on the very thing she’s always feared.
The countdown hasn’t just begun; it’s rapidly reaching the end—the end of an epoch, the end of the human era. And it might already be too late to stop it.
The final installment of the 6TH EXTINCTION Post-Apocalyptic series from Tara Ellis! This series explores every facet of global disasters and how far people will go to survive. It's perfect for fans of Kyla Stone, Bobby Akart, Jack Hunt, and Ryan Schow.
Get it now!
With the Earth in ruins from three catastrophic impacts, surviving the fallout was only the beginning. Unleashed from its celestial vector, the Prometheus Pathogen ravages those left behind, revealing how controlling life and death is a trait that will always be a driving force. As science advances, so does the threat of wielding that power.
Caught in the fight to access a potential cure, Kyle risks everything he has left to secure a future for his daughter, but the most lethal obstacles are those he can’t see coming. When lines are blurred, the way out may not always be straightforward.
Dallas has spent a lifetime navigating the unknown, though nothing could prepare her for the role she was to assume at the end of a civilization. Thrust into the chaos with an unlikely team, surviving will come down to her ability to trust and rely on the very thing she’s always feared.
The countdown hasn’t just begun; it’s rapidly reaching the end—the end of an epoch, the end of the human era. And it might already be too late to stop it.
The final installment of the 6TH EXTINCTION Post-Apocalyptic series from Tara Ellis! This series explores every facet of global disasters and how far people will go to survive. It's perfect for fans of Kyla Stone, Bobby Akart, Jack Hunt, and Ryan Schow.
Get it now!
300 pages, Kindle Edition
Published September 9, 2025
225 people are currently reading
16 people want to read
About the author
Tara Ellis
64 books250 followersWith over 50 published books across ten genres, author Tara Ellis is best known for her heart-pounding post-apocalyptic and thriller series. A heavy dose of mystery often underscores her character-driven plots, heralding back to what fueled her desire to tell stories from an early age.
A certified firefighter in the state of Washington, Tara volunteered as a FF/EMT for over eight years. She also responded as a support officer, worked as an emergency room technician, was a 911 dispatcher, and taught life-saving techniques to the public and first responders. As an author of thriller and survival stories, she draws upon her personal experience throughout her storytelling.
Tara lives in the gorgeous Cascade Mountains of Washington State. When not writing or spending time with family, she can be found hiking the woods while plotting her next adventure.
*Join Tara's newsletter on her author website: Tara Ellis Books
*Check out her women's literature and mysteries under the pen name of Tara Meyers
*Find her on FB under Tara Ellis Author
Check back for upcoming dates for public appearances and book signings!
Coming this year, in 2025:
*A new post-apocalyptic series with Aethon Books, The 6th Extinction, releases in April
*A new thriller series co-authored with L.T. Ryan was announced to release later this year!
*The third and final book in The Fallen series, The Redeemed, is coming this summer
*Several new audiobooks will go live throughout the year
Check back for upcoming dates for public appearances and book signings!
A certified firefighter in the state of Washington, Tara volunteered as a FF/EMT for over eight years. She also responded as a support officer, worked as an emergency room technician, was a 911 dispatcher, and taught life-saving techniques to the public and first responders. As an author of thriller and survival stories, she draws upon her personal experience throughout her storytelling.
Tara lives in the gorgeous Cascade Mountains of Washington State. When not writing or spending time with family, she can be found hiking the woods while plotting her next adventure.
*Join Tara's newsletter on her author website: Tara Ellis Books
*Check out her women's literature and mysteries under the pen name of Tara Meyers
*Find her on FB under Tara Ellis Author
Check back for upcoming dates for public appearances and book signings!
Coming this year, in 2025:
*A new post-apocalyptic series with Aethon Books, The 6th Extinction, releases in April
*A new thriller series co-authored with L.T. Ryan was announced to release later this year!
*The third and final book in The Fallen series, The Redeemed, is coming this summer
*Several new audiobooks will go live throughout the year
Check back for upcoming dates for public appearances and book signings!
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Displaying 1 - 8 of 8 reviews
September 10, 2025
Exhilarating and worth the wait!
Critical Mass, book 3 in the 6th Extinction series, is an absolute thrill ride and an exhilarating read! The writing is beautifully composed, with great characters, unending suspense and a surprise ending. That's all I'll say, I don't want to spoil the fun for anyone else. 5/5 stars, with the highest recommendation! If you enjoy apocalyptic survival thrillers, put Critical Mass at the top of your 'to read' list!
Critical Mass, book 3 in the 6th Extinction series, is an absolute thrill ride and an exhilarating read! The writing is beautifully composed, with great characters, unending suspense and a surprise ending. That's all I'll say, I don't want to spoil the fun for anyone else. 5/5 stars, with the highest recommendation! If you enjoy apocalyptic survival thrillers, put Critical Mass at the top of your 'to read' list!
September 9, 2025
This has been an exciting series, with this finale taking it to another level for intense and emotional scenes. I loved how Tara built the tension and then followed through with the action, delivering a truly satisfying ending to this remarkable trilogy l can highly recommend this book and series, as well as all of Tara’s works.
September 12, 2025
Critical Mass
Well this was different but very enjoyable to read. Amazing how they all got together to work things out. I thought the plot well thought out.
September 14, 2025
Ripped through this story!
This was a non stop romp through what could happen to the planet. Sometimes it got a little too ‘out there’, but what should I have expected from a sci-fi apocalyptic from this author and her colleagues. 😊
This was a non stop romp through what could happen to the planet. Sometimes it got a little too ‘out there’, but what should I have expected from a sci-fi apocalyptic from this author and her colleagues. 😊
November 1, 2025
Great series. Listened to the first two books, 3rd not available yet. I am glad I read the 3rd book.
December 4, 2025
Different take on the apocalypse
A throughly enjoyable read across a 3 books in this series..it's nice to not have zombies or emp's as the coause of man's downfall.
A throughly enjoyable read across a 3 books in this series..it's nice to not have zombies or emp's as the coause of man's downfall.
September 23, 2025
Survival!
I liked the happy ending. I didn't like the character development of Alex and even Drew. I am glad the main characters survived. Just not feeling the connection as much as I didn't in the previous books.
I liked the happy ending. I didn't like the character development of Alex and even Drew. I am glad the main characters survived. Just not feeling the connection as much as I didn't in the previous books.
October 1, 2025
This is a good addition to a good series. Alex Winchester is a bit too much of a stereotypical evil and one-dimensional doctor for my taste, but this story did unfold nicely. It also wrapped up well to finish the series and I enjoyed reading this.
Displaying 1 - 8 of 8 reviews