John Wayne Gary publicly urged the grieving mother of one of his victims to kill herself with a drug overdose.

In this archive footage, Gacy jovially demonstrates to a naïve TV reporter "how to tie knots" - giving a glimpse of how he captured victims.

John Wayne Gacy's paintings have become highly sought after in the 'murderabilia' world - but they have also caused a lot of distress.

'Killer Clown' John Wayne Gacy revealed why he invented Pogo and how he found wearing clown-face makeup relaxing

Before his reign as a child-killing clown, John Wayne Gacy had a stint working at a mortuary

The Yorkshire Ripper Peter Sutcliffe and necrophile child molester Jimmy Savile struck up an uncomfortable friendship in the late 1980s...

Zachary Davis killed his mum and tried to set his brother on fire - but later claimed he did't do it - and it was the fault of his sibling.

We all went to school with at least one weirdo... but did any of your former classmates bludgeon their mum to death with a sledgehammer...

The teen tells Dr. Phil how he bludgeoned his mum to death with a sledgehammer as she slept... you won't be able to un-see this!

In 2000, Katherine Knight was the first woman in Australia to be given a full-life sentence without parole - this is her life now.

These are the best True Crime books ever written - do you agree? Tell us @sinisterisles

Ed Kemper's brother lives in fear that his huge murderous sibling will use his IQ to get out of prison... and hunt him down and kill him.

Cindy Haden was one of the jurors at Richard Ramirez’s 1988 trial, and she took a real shine to the Devil worshipping sodomising burglar.

After Edmund Kemper killed and decapitated his mother, he tore out her vocal cords and shoved them down the waste disposal.

These days, serial killer groupies have the internet to share their thoughts, feelings and desires - in the 90s they went on TV.

For 19 years, Marie Noe was the most pitied woman in America - every single one of her ten babies had died between April '49 and January '68

Sex-crazed abattoir worker Katherine Knight is a very rare female psychopath.

There have been few photos of Ed Kemper since he was jailed in 1973 for eight counts of murder - including that of his own mum... until now

"The perfect calendar doesn't ex... of wait" Etsy Customer It's here! The calendar you never knew you wanted (or existed for that...

He confessed that he had lured boys to his home where he sodomised them, strangled, dismembered, and dissolved them in acid.