ITV's most recent drama tells the chilling story of real-life serial killer Dennis Nilsen and the shocking murders that he committed in North London.
Starring David Tennant in the lead role, the story goes into great detail about Nilsen's killing spree and his gruesome past.
And now it's been revealed that when Nilsen was serving in the British Army in Germany in the 1960's, his dark sexual fantasies began to manifest.
According to reports, during his time there Nilsen would often drink with his fellow soldiers and pretend to be unconscious in the hopes that they would have sex with him.
When he was stationed in the State of Aden as an army chef he had his own room, where it is believed he developed his dark masturbation technique.
Nilsen allegedly looked at his own naked body in the mirror as he lay flat on his chest, pretending to be unconscious.
The killer used a free-standing mirror and placed it in a certain position so he couldn't see his own face, allowing him to pretend he was having sex with someone else.
Nilsen apparently imagined his own near death experience at war and the dead bodies he had seen during conflicts.
The revelation comes after it emerged how Nilsen's victims were found at two different addresses in North London following his killing sprees.
Nilsen's murders were first discovered by a Dyno-Rod employee, Michael Cattran, who responded to the plumbing complaints made by both Nilsen and other tenants of 23 Cranley Gardens on February, 8, 1983.
Opening a drain cover at the side of the house, Cattran discovered the drain was packed with a flesh-like substance and numerous small bones of unknown origin.
Upon hearing Cattran exclaim how similar the substance was in appearance to human flesh, Nilsen replied: "It looks to me like someone has been flushing down their Kentucky Fried Chicken."
Following another inspection, Cattran decided to go to the police and report the suspicious behaviour which led to them paying Nilsen a visit.
Three policeman visited Nilsen at his flat and upon entering, they immediately noted the odour of rotting flesh and explained to Nilsen what had been found in the drains.
The former security guard attempted to act shocked at first, but the police were having none of it and told Nilsen: "Don't mess about, where's the rest of the body?"
Nilsen is said to have responded calmly, admitting that the remainder of the body could be found in two plastic bags in a nearby wardrobe.
The officers did not open the cupboard, but asked Nilsen if there were any other body parts to be found, to which Nilsen replied: "It's a long story; it goes back a long time. I'll tell you everything. I want to get it off my chest. Not here - at the police station."
He was then arrested and cautioned on suspicion of murder, before being taken to Hornsey police station.
As he was escorted to the police station, Nilsen was asked whether the remains in his flat belonged to one person or two.
Staring out of the window of the police car, he replied: "Fifteen or sixteen, since 1978".