Government mathematician Chris Barton lives a routine life-until, at the end of an ordinary workday, he finds his car missing from the employee parking lot. When he finally arrives home, there is a stranger living in his house-a man who claims to be him. Thrust suddenly into a surreal world where the evidence of his senses cannot be trusted and strangers are trying to kill him, Chris must avoid violent assassins while following a trail of cryptic clues to regain his life.