Two strangers meet on a train. They’ve never met before. Both of whom have someone they’d like to murder. So, they swap murders. A psychopath shares this concept with tennis star Guy Haines, whose wife refuses to get a divorce. He agrees, thinking it is a joke. But now his wife is dead, Haines finds himself a prime suspect and the man wants Guy to kill his father.

Larry Donner, an author with a cruel ex-wife, teaches a writing workshop in which one of his students, Owen, is fed up with his domineering mother. When Owen watches a Hitchcock classic that seems to mirror his own life, he decides to put the movie's plot into action and offers to kill Larry's ex-wife, if Larry promises to murder his mom. Before Larry gets a chance to react to the plan, it seems that Owen has already set things in motion.

A woman seduces a professional golfer, then offers to kill his opponent if the golfer will kill her psychiatrist, who wants her committed.