
Some of the world's most notorious murders are the subject of "It Takes a Killer," which investigates the crimes from the perspective of the killers, trying to get inside their minds and determine their motives. Leading homicide investigators and experts from such agencies as the FBI and Scotland Yard take a look at the evidence pulled from crime scenes and profile the killer's behavior to try to piece together the details of each murder, explaining when, why and how each criminal committed the crime. For the wannabe detectives watching the show, the experts also reveal how the crime was solved -- which often requires authorities to think like a killer.

A jealous bodybuilder who paid to have his rival killed turns up half a world away after a decade of hiding from law enforcement.

The police scramble to find a trucker serial killer who crosses the country hunting for victims.

Two ex-marines join forces for one sole nefarious purpose - to abduct women and keep them a sex slaves; carrying out their operation with military precision, unafraid to kill innocent civilians along the way.

The disappearance of a decorated military man stumps law enforcement and shocks a central Texas community, but once investigators dig into his home life, they uncover a vicious murder plot involving his veterinarian wife.