A psychological thriller with a reality-bending twist: every suspect is an alternate version of the same man.

Joshua Hoffman is hosting a fortieth birthday party at his secluded lakeside home, but the guests are no ordinary attendees-they are nine alternate versions of himself from other timelines, all brought together by cutting-edge technology. Each has taken a different path through life. Each has ended up with a very different fate.

Among them are: The Argentinian, who fled his dreary hometown for a life of luxury in South America; The Townie, who stayed behind to marry his high school crush; The Marksman, a single father struggling to raise his troubled daughter; The Director, a Hollywood filmmaker facing an embarrassing end to his career; and The Teacher, a man of faith and moral duty.

But after a raucous night of one-upmanship, one of the Joshua Hoffmans is found brutally strangled. Now, the others must face a terrifying reality: a killer is among them-and his name is Joshua Hoffman.

As the violence escalates and bodies pile up, the group must uncover the murderer by answering a simple, chilling question: which Joshua Hoffman wants to kill his other selves, and why?