Following a bitter separation from his wife, famed mystery writer Mort Rainey is unexpectedly confronted at his remote lake house by a dangerous stranger named John Shooter. Claiming Mort has plagiarized his short story, the psychotic Shooter demands justice. When Shooter's demands turn to threats, and then to murder, Mort turns to a private detective he knows. But when nothing stops the horror from spiraling out of control, Mort soon discovers he can't trust anyone or anything.