Detective sergeant Chris Healey first heard the name Nilsen while sat at his desk on a February afternoon in 1983. The previous day, what looked like human remains had been discovered in a drain outside a house in Muswell Hill, north London. The occupant, a mild-mannered civil servant called Dennis Nilsen, calmly told investigators that the flesh belonged to men he had murdered. As he was driven away in a police car, Nilsen bragged that he had killed as many as “15 or 16 since 1978” - a number that immediately divided opinion among the investigation squad convened that afternoon.
“I was a bit sceptical,” remembers Healey, 69, from his home in Bournemouth. “A lot of people thought at the time that he was a fantasist and that couldn't be the case.” But, soon enough, officers discovered more than 1,000 fragments of human tooth and bone at Nilsen’s old flat in Cricklewood, where he lived until 1981.
The case was among the most baffling of Healey’s 31-year career - although, having already worked on terrorist investigations during The Troubles, he did not find it all that gruelling. The memories are particularly fresh this week, following the conclusion of the well-received ITV drama, Des, which tells the story of the investigation into Nilsen, a floppy-haired former policeman who later worked at a job centre in Kentish Town. He is thought to have murdered 15 young men between 1978 and 1983, making him Britain’s second-most prolific criminal, after Harold Shipman. He preyed on rootless drifters, some of whom were homeless, meeting them in pubs or gaming arcades before inviting them back to his flat, where he usually strangled them, or drowned them in his bathtub. Of the 15 Nilsen claimed to have murdered, only seven were ever identified. He was sentenced to life in prison with a minimum of 25 years, which was upped in 1994 to a whole-life tariff. He died in 2018.
Healey thinks the TV drama does an excellent job of conveying the sheer grisliness of those crimes. He remembers searching Nilsen’s flat the morning after his arrest and finding a pair of human legs in the bathroom. Exhibits would usually be removed from the house in evidence bags, but, with photographers outside, Healey and his colleagues instead placed the torso in a coffin. He later learnt that the torso belonged to 20-year-old Stephen Sinclair, an Australian tourist with drug issues whose disappearance had prompted considerable interest from the press. Nilsen preyed on Sinclair as he walked down Oxford Street in January 1983, offering to buy him a hamburger before inviting him back to his flat, where he strangled him with a rope while listening to the rock opera, Tommy.
In Des, Healey is played by Jay Simpson, of Foyle’s War fame - although Healey jokes that he is “not as cockney” as his on-screen equivalent. One detail of the TV drama that is more accurate, he says, is the constant cigarette smoking: “Virtually everyone smoked in those days, it was like a fog inside the office.”
Healey was particularly impressed by David Tennant’s depiction of Nilsen, which perfectly conveyed the killer’s unnervingly nonchalant, almost affable demeanour, he thinks. “He didn’t seem to be fazed about it at all. You’d think you might fear that you’re next to a mass murderer, but it wasn’t like you’ve got Hannibal Lecter next to you. He was very civil, you could chat to him.”
Indeed, the killer used to crack all manner of bizarre jokes at his interrogators’ expense. At one point, Healey took Nilsen for a doctor’s examination - various scratches had been found around his body, and police thought they may have been put there by his victims, trying to fight him off in their dying moments. The doctor told Nilsen to drop his cigarette down the sink, because there weren’t any ashtrays. Nilsen responded: “Are you sure you want me to do that? The last time I put something down the drain, it ended up being nicked.”
Healey remembers: “You just couldn’t believe he had that sense of humour when he’s been arrested and he’s got 15 bodies hanging over his head.”
The 35-member investigation squad was led by Detective Chief Inspector Peter Jay, depicted in the ITV drama by Daniel Mays as a passionate, fire-breathing boss who shouts at his juniors when he discovers that somebody has leaked information to the press. But Healey remembers the real Jay, who died in 2018, as a “very calm, cool, and collected man, very softly spoken. I don't think I can recall him ever shouting. If you'd done something wrong, he wouldn't give you a bollocking, he would get you in his office, and then quietly explain. He was a clever man, always on top of everything.”
Their strategy was to “kill [Nilsen] with kindness” so he would keep talking, an approach that irritated some officers. They were also keen to learn about his background, and potential motivations. To this end, Healey was dispatched to Aberdeenshire, where Nilsen grew up, to meet his mother, a “lovely lady” who cooked Healey a chicken lunch. She reminded him of Janice, the preternaturally calm housekeeper in the Sixties BBC drama, Dr Finlay’s Casebook.
There, they delved into Nilsen’s life. Healey learnt how close Nilsen had been to his maternal grandfather (his father, Olav, was mostly absent), and how withdrawn he became after his grandfather’s death. They probably discussed Nilsen’s service with the Royal Fusiliers in west Germany, in the Sixties; and how he drifted away from his family after an explosive argument in 1972, in which Nilsen’s brother outed him as gay to the rest of the family.
The TV drama, written by Luke Neal, hints at a sense of guilt among some officers that Nilsen was allowed to get away with the murders for so long - right “on our patch”, as Mays’s character puts it in an emotional outburst. Healey says there is some truth there, especially when they learnt that, at one point in the years before Nilsen's arrest, a man told police that Nilsen tried to strangle him. The police spoke to Nilsen at the time, but he was able to talk it away as a “lover’s tiff”, Healey says. “At one stage it was thought, hang on, the police have made a cock-up here, if [the accuser] had been interviewed at an early stage, then perhaps this wouldn’t have happened. There was a feeling of, How could this have gone on?.”
But a subsequent investigation found that officers had tried to contact the accuser three times, and he was never home. And many of Nilsen’s victims led lives of such rootless anonymity that, tragically, nobody noticed they had gone missing, making it difficult for police to spot the pattern.
Most victims were gay, and the investigation tested the police’s historically fraught relationship with London’s gay community. “One thing that would happen now, which they didn’t have in those days, was a gay liaison officer,” Healey says. “You had all these [officers] trooping down from Hornsey to go around the pubs of the West End [to find potential witnesses] and they didn't know really which ones were gay pubs and which ones weren't.” But the police also showed moments of understanding. One witness, student Paul Nobbs, whom Nilsen had attempted to strangle in 1981, was not yet out as gay to his parents, and officers went out of their way to help Nobbs keep his secret, Healey remembers.
It was an act of humanity for one of the few surviving victims - humanity that Dennis Nilsen, in all his arrogance and bluster, had so cruelly denied them.