During a police interrogation for a man's murder, the suspect makes a jarring confession; a car thief makes a startling admission of murder, the details of which prove that he had no mercy for the victim.

Police interview a man suspected of murdering a beloved clergy member and learn the victim was his loyal friend; at a church service, a teen confesses to a vile murder.

An Iowa man describes in bone-chilling detail the horrors he inflicted on his doting parents; a mother reports her violent son, Chris, to police just days before they find her dead.

A man sobs tearlessly as he recounts finding his girlfriend and her mother murdered at home, but his act doesn't sit right with detectives; an arrogant man relives the day a routine visit results in three deaths.

A man casually details to police how he killed his wife and later drops a bombshell about a 1988 cold case murder; a Michigan woman's bludgeoning death leads police to her fiancé, a career criminal who served time for a suspected 1,200 crimes.

A passenger's death in a car accident seems cut and dry -- until police notice the stab wounds; all eyes are on the driver; the brutalized body of a disabled man sends police on the heels of a woman who seemingly thirsts for torture.

A look inside the mind of psychopaths to discover when common pervasive traits deviate into violence, such as grandiosity, sadism, superficial charm, manipulation, lack of empathy and having a parasitic lifestyle.

When a priest from Florida goes missing, police focus on a troubled ex-convict whom he helped support; through multiple interrogations, a psychopathic killer reveals details of a twisted vengeance that escalates to a chilling murder.

Omaha police officers chase down a stolen vehicle driving recklessly. When they arrest the driver, he shocks detectives by giving an unsolicited confession to a gruesome murder of a local woman, the first of many chilling revelations.

A beloved elderly couple disappears on a Sunday afternoon. One person knows their battered bodies lie dead at the bottom of a well. That man is the couple's son, who lives off of his parents' charity yet takes sadistic pleasure in murdering them.

Behind a church lies a dismembered body burned beyond recognition. Investigators identify the victim by fingerprints and receive a tip the suspect is female. A police interview reveals her as the most remorseless psychopathic killer they've ever seen.

A man who reported the murder of his girlfriend and her mother is in for a plot twist after authorities discover his desire for revenge on her.

A man confesses that he "accidentally" killed his best friend while cleaning his gun. During his interrogation, he stuns police by revealing that he's behind a long trail of bloodshed and is a serial killer who seems to consider himself an angel of mercy.

After his conviction for the brutal slaying of his wife, a Florida inmate lays claim to another unsolved murder 17 years prior, revealing that he's a manipulative psychopath with a history of violence and an unquenchable thirst for revenge.

Searchers for a missing woman find her brutally beaten body in a dilapidated house near her home. The case goes cold until a local teen steps forward to reveal that he's not only the killer but also a manipulative psychopath with a thirst for violence.

A crash on a North Dakota highway leaves one passenger dead but the driver unscathed. When investigators see that the victim has stab wounds, they know there was foul play. Detectives interrogate the driver and quickly realize he's a psychopath.

A mother who calls 911 to report her 32-year-old son is threatening her turns up dead in her home. He becomes the only suspect, and when he turns himself in, his pragmatic retelling of the slaying isn't just cold-hearted, it's psychopathic.

When Father Rene Robert goes missing, a desperate search ensues that spurs car chase and the arrest of a disturbed man who reveals a story of kidnapping and murder.