Season 4

"The Perfect Murder" brings viewers some of the most diabolical, perplexing murder cases to land on detectives’ desks – the kind of cases that make or break careers and provide fodder for Hollywood mystery movies. These ingenious killers are every detective’s worst nightmare. Whether by planting false evidence, or writing anonymous letters to police, these murderers will stop at nothing to stay one step ahead and get away with the perfect murder. Detectives hit dead end after dead end, and wrong suspects are discarded. But one new clue can lead to another and the cold case suddenly gets hot. The truth is that it is the perfect murder -- until it's not.