The Probability of Time

The Arrowhead Killer is dead! After a decade of hunting the city of Grimwick’s most notorious serial killer, Detective Liam Smart finally feels the colossal weight of this case lift from his shoulders. Justice for the killer’s fifteen victims has been served — or so he thought.

When a new victim is discovered, Liam fears the killer may have had an apprentice — or worse, he arrested the wrong man. Determined to bring swift justice, he enlists the help of Lorelei, a young, enthusiastic historian who may have knowledge vital to unlocking this new mystery.

But as the case’s evidence begins to build, Liam quickly discovers Lorelei isn’t just beautiful and smart, she has a secret. And the longer he pursues the killer, the more he gets dragged into the middle of a secret war that’s responsible for reshaping the American political landscape until he has no choice but to join the fight.

The Probability of Time is the first book in The Historians trilogy: a steamy, action-packed thriller about time travel, alternate history, and American secret societies dating back to the Revolutionary War.

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“Law and Order meet Doctor Who, with a dash of conspiracy, murder, and betrayal. It’s hard to know who to trust when time is a plaything.”
Amazon Reviewer

“I almost finished the book in one sitting. It is a wonderful and surprising story with twists and turns you will never expect. It is a thriller, a detective story, a love story, making you think a lot about what is real and what is not.”
Language5, Amazon Reviewer

What a story! This is not your typical mystery, crime drama, or science fiction. It’s a beautiful mixture of all of these genres. The author grabs your attention from page one and right when you think “oh, I know where this is going.” He throws another twist that keeps me hooked to reading more. It’s an enjoyable read, excited for what comes next!
Janet Smith, Amazon Reviewer

This book is amazing and such a good read I can’t put it down seriously. This book helped me read again for the first time in years. And it was not only suspenseful but exciting and fun as well! Definitely recommend to anyone who’s looking for a good adventure 🙂
Liz, Amazon Reviewer

“A unique approach to time travel. Koster allows us to sneak up on it and BAM! you’re hot in the middle of a story that will not let go until it turns you inside out. Get ready for the end! I’m anxiously awaiting the next book!”
M E Keyes, Amazon Reviewer

“A great book with many twists and turns. Reminiscent of National Treasure and Doctor Who.”
Amazon Reviewer

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