
A book by Jack Mars
Expected release date: February 6, 2026
Countdown Zero (Agent Zero Spy Thriller #18) releases in:
- Tag You’re ItJanuary 30, 2026 — in 7 days
- Wicked Altar (The McCarthy Family Legacy)January 30, 2026 — in 7 days
- Fairy Tale Finale (Backstage Mirror #3)January 30, 2026 — in 7 days
- Brawling Hearts (Pine Valley College #4)January 30, 2026 — in 7 days
- The Fifteen-Minute Rule (Dickson University #3)January 30, 2026 — in 7 days
- So Ruthless (Faith Bold #27)January 30, 2026 — in 7 days
‘You will not sleep until you are finished with AGENT ZERO. A superb job creating a set of characters who are fully developed and very much enjoyable. The description of the action scenes transport us into a reality that is almost like sitting in a movie theater with surround sound and 3D (it would make an incredible Hollywood movie). I can hardly wait for the sequel.’
–Roberto Mattos, Books and Movie Reviews
COUNTDOWN ZERO is book #18 in the #1 bestselling AGENT ZERO series, from #1 bestselling and USA Today bestselling author Jack Mars (with over 10,000 five-star reviews). The series begins with AGENT ZERO (Book #1), a free download.
Beneath the ocean’s surface lurks a submarine gone rogue, threatening coastal chaos with hypersonic missiles unless their ransom demands are met.
With only 24 hours to halt the countdown to devastation, Agent Zero must navigate a deadly game of cat and mouse beneath the waves—a game where one wrong move could lead to catastrophic consequences.
The AGENT ZERO saga offers a gripping journey packed with unexpected turns and dynamic action, keeping you enthralled from start to finish. At the core of this thrilling series is an engrossing relationship between a father and his daughter, which is sure to keep you reading voraciously until the early hours.
Books #19–#24 in the series are also available!
‘Thriller writing at its best.’
–Midwest Book Review (Any Means Necessary)
⭐⭐⭐⭐⭐
‘Thriller enthusiasts who relish the precise execution of an international thriller, but who seek the psychological depth and believability of a protagonist who simultaneously fields professional and personal life challenges, will find this a gripping story that’s hard to put down.’
–Midwest Book Review, Diane Donovan (regarding Any Means Necessary)
⭐⭐⭐⭐⭐
‘One of the best thrillers I have read this year. The plot is intelligent and will keep you hooked from the beginning. The author did a superb job creating a set of characters who are fully developed and very much enjoyable. I can hardly wait for the sequel.’
–Books and Movie Reviews, Roberto Mattos (re Any Means Necessary)
⭐⭐⭐⭐⭐
Genre: Thriller
Like Countdown Zero (Agent Zero Spy Thriller #18)? Readers also searched for these releases





































