Harvey Mapes is a 26-year-old security guard who spends his nights in a guard shack outside a gated community in Southern California, reading detective novels, watching reruns, and waiting for his life to finally start ... which happens when Cyril Parkus, one of the wealthy residents, asks Harvey to follow his beautiful wife. The lowly security guard jumps at the opportunity to fulfill his private eye fantasies and learn everything he's learned from his books, but he soon discovers that the differences between fiction and reality can be deadly.