Dennis Nilsen’s disturbing solo sex act fantasy as he pretended to be dead

Dennis Nilsen’s disturbing reign of terror is about to depicted in a chilling ITV series starring David Tennant, called Des.

The serial killer murdered at least fifteen young men and boys between 1978 and 1983 in London.

But before he would start his terrible killing spree, Nilsen satisfied his disturbing desire with bizarre masturbation rituals.

In the early 1960s he joined the army and served as a private in West Germany.

It was during this time that he started developing dark sexual fantasies about being with an unconscious or dead partner.

During his time in the army he would often drink with his fellow soldiers and pretend to be unconscious in the hopes 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 he developed his dark masturbation technique.

He looked at his own naked body in the mirror as he lay flat on his chest, pretending to be unconscious.

Nielsen used a free-standing mirror positioned so he couldn’t see his own face, allowing him to pretend he was having sex with someone else.

The killer would imagine his own near death experience at war and the dead bodies he had seen during conflicts.

He moved to London in the 1970s where he briefly worked as a police officer, before finding work as a security guard and then at a Jobcentre.

His killing spree began in 1978 and his dark sexual desires were played out during the killings.

Nielson would lure his victims to his home to strangle and drown them, ­keeping the corpses for ­several weeks and performing disgusting sex acts on them.

After cutting up the bodies, he burned the parts in his ­garden or flushed them in his toilet.

His first victim was 14-year-old Stephen Holmes on December 30 1978.

Nielsen lured him back to his home and attempted to strangle him before drowning him in a bucket of water, keeping his body hidden under his floorboards for eight months.

Next he killed Kenneth Ockenden on December 3, 1979, a 23-year-old Canadian student who he invited back to his flat for dinner before strangling him with a headphone cord.

He murdered Martyn Duffey, 16, on May 17, 1980, before bathing with his body in a bathtub.

William Sutherland, 26, was killed in August 1980 but Nielsen said he didn’t remember much about the murder.

Malcolm Barlow, 23, was murdered on September 18, 1981.

In March 1982 he strangled John Howlett, 23, while he slept and then drowned him in the bath.

Graham Allen, 27, was murdered that September and parts of his body were found in a drain.

Stephen Sinclair, 20, was the final known murder victim and he was killed on January 26, 1983.

Nilsen was caught in 1983 when a man sent to clear his blocked drains discovered flesh.

Police would later find shopping bags full of body parts and ­organs in his home.

Nilsen also admitted boiling heads in a cooking pot on his stove to dispose of the brains.

He was found guilty of six counts of murder and one of attempted murder.

In November 1983 Nilsen was sentenced to life imprisonment with a recommendation that he serve a minimum of 25 years.

He died in May 2018 at HMP Full Sutton in East Yorkshire.

*Des airs tonight on ITV at 9pm