Dubbed "the Grindr Killer", serial rapist Stephen Port murdered at least four men by using gay social networks to find his victims.
The case of the cannibal cop killer, Stefano Brizzi, who murdered and consumed part of a police officer he met through a dating app.
An examination of Mick Philpott, the notorious Derby father of 17 who murdered six children, five of them his own, when he set his own home on fire.
In 2012, April Jones disappeared from outside her home in Wales, never to be seen again. Her abductor, and murderer, was found to be Mark Bridger.
A profile of child killer Roy Whiting, the convicted sex offender who abducted and murdered eight-year-old Sarah Payne.
What drove Raoul Moat to shoot his ex-girlfriend, her new lover and a policeman, leading to the largest manhunt in modern British history?
