
An in-depth look at some of the world's most dangerous murderers.

Experts look back on the crimes of John Cannan as he moved in and out of prison.

After striking up a friendship in prison for previous murders, Stephen Unwin and William McFall's release had awful consequences.

A serial killer works as a nurse in Texas, where she kills many children and infants by injecting them with drugs.

A cold-blooded serial killer takes the lives of eleven people during a terrifying decade-long murder campaign.