Following each murder, Nilsen would perform a ritual in which he bathed and dressed the victim's body, which he retained for extended periods of time, before dissecting and disposing of the remains by burning them in a bonfire or flushing them down a toilet.
His father did not view married life with any seriousness, being preoccupied with his duties with the Free Norwegian Forces and making little attempt to spend much time with or find a new home for his wife.
Nilsen passed the entrance examinations and received official notification he was to enlist for nine years' service in September 1961, commencing his training with the Army Catering Corps at St. Omer Barracks in Aldershot, Hampshire.
[23] He relished the travel opportunities afforded him in his training and recalled as a highlight his regiment taking part in a ceremonial parade attended by both the Queen and Field Marshal Lord Montgomery of Alamein.
[26] Following two years of service in Osnabrück, Nilsen returned to Aldershot, where he passed his official catering exam before being deployed to serve as a cook for the British Army in Norway.
[30] In Nilsen's most vividly recalled fantasy, a slender, attractive young blond soldier who had been recently killed in battle is dominated by a faceless "dirty, grey-haired old man" who washed this body before engaging in intercourse with the spreadeagled corpse.
On more than one occasion in the three months Nilsen lived in Strichen, his mother voiced her opinion as to her being more concerned with his lack of female companionship than his career path, and of her desire to see him marry and start a family.
The two men spent the evening drinking and talking; Nilsen learned that Gallichan had recently moved to London from Weston-super-Mare, Somerset, was gay, unemployed, and residing in a hostel.
[n 3] Initially, Nilsen experienced domestic contentment with Gallichan, but within a year of their moving to Melrose Avenue, the superficial relationship between the two men began to show signs of strain.
If the victim had been strangled into unconsciousness, Nilsen then drowned him in his bathtub, his sink, or a bucket of water before observing a ritual in which he bathed, clothed, and retained the bodies inside his residences for several weeks or, occasionally, months before he dismembered them.
[70][n 4] On 11 October 1979, Nilsen attempted to murder a student from Hong Kong named Andrew Ho, whom he had met in a St Martin's Lane pub and lured to his flat on the promise of sex.
[71] Two months after the attempted murder of Ho, on 3 December 1979, Nilsen encountered a 23-year-old Canadian student named Kenneth Ockenden,[72] who had been on a tour of England visiting relatives.
Duffey was a catering student from Birkenhead, Merseyside, who had hitchhiked to London without his parents' knowledge on 13 May after being questioned by the British Transport Police for evading his train fare.
On or about 4 January 1981, Nilsen encountered an unidentified man whom he described to investigators as an "18-year-old, blue-eyed" young Scot[88] at the Golden Lion pub in Soho; he was lured to Melrose Avenue upon the promise of partaking in a drinking contest.
For almost two months, any acquaintances Nilsen encountered and lured to his flat were not assaulted in any manner,[44] although he did attempt to strangle a 19-year-old student named Paul Nobbs on 23 November 1981,[97] but stopped himself from completing the act.
On three occasions over the following ten minutes, Nilsen unsuccessfully attempted to kill this victim after noting he had resumed breathing, before deciding to fill his bathtub with water and drown him.
At the flat, Stottor consumed further alcohol before falling asleep upon an open sleeping bag; he later awoke to find himself being strangled with Nilsen loudly whispering, "Stay still".
Three months after Nilsen's June 1982 promotion to the position of executive officer in his employment, he encountered a 27-year-old named Graham Allen attempting to hail a taxi in Shaftesbury Avenue.
[111] As had been the case with both Howlett and Allen, Sinclair's body was subsequently dissected, with various dismembered parts wrapped in plastic bags and stored in either a wardrobe, a tea chest, or within a drawer located beneath the bathtub.
Both men immediately called the police who, upon closer inspection, discovered further small bones and scraps of what looked to the naked eye like either human or animal flesh in the same pipe.
"[119] Nilsen responded calmly, admitting that the remainder of the body could be found in two plastic bags in a nearby wardrobe, from which DCI Jay and his colleagues noted the overpowering smell of decomposition emanated.
Assembling the remains of the victims killed at Cranley Gardens on the floor of Hornsey mortuary, Professor Bowen was able to confirm the fingerprints on one body matched those on police files of Sinclair.
The torsos and limbs of the three victims killed at this address were dissected within about one week of their murder before being wrapped in plastic bags and stowed in the three locations he had indicated to police; the internal organs and smaller bones he flushed down the toilet.
The defence counsel, Ivan Lawrence QC, argued that Nilsen suffered from diminished responsibility, rendering him incapable of forming the intention to commit murder, and should therefore be convicted only of manslaughter.
[147] Upon cross-examination, the defence counsel sought to undermine Stewart's credibility, pointing to minor inconsistencies in the testimony, the fact he had consumed much alcohol on the night in question, and suggesting his memory had been selectively magnified as he had previously sold his story to the press.
[163][n 11] In December 1983, Nilsen was cut on the face and chest with a razor blade by an inmate named Albert Moffatt, resulting in injuries requiring eighty-nine stitches.
Central Television challenged the Home Office ruling in court, citing sections of the Copyright, Designs and Patents Act 1988, and that full permission to conduct an interview with Nilsen had been granted in advance.
[178] Formal identification was confirmed via a combination of circumstantial evidence and by Nilsen identifying a photograph of the youth shown to him by police (all bone fragments found at Melrose Avenue had been destroyed).
[181][182] In January 2021, a former confidant of Nilsen's named Mark Austin revealed that an edited version of The History of a Drowning Boy was to be posthumously published by RedDoor Press.
Nilsen said that three unidentified victims he had initially confessed to killing – an Irishman in September 1980; a "long-haired hippy" in November or December 1980, and an English skinhead in April 1981 – had been invented to simply "complement the continuity of evidence".