Dennis Andrew Nilsen (23 November 1945 – 12 May 2018) was a Scottish serial killer and necrophile who murdered at least twelve young men and boys between 1978 and 1983. Convicted at the Old Bailey of six counts of murder and two of attempted murder, Nilsen was sentenced to life imprisonment on 4 November 1983, with a recommendation that he serve a minimum of 25 years; this recommendation was later changed to a whole life tariff in December 1994. In his later years, Nilsen was imprisoned at HM Prison Full Sutton in the East Riding of Yorkshire.
All of Nilsen's murders were committed at the two North London addresses where he lived between 1978 and 1983. His victims were lured to these addresses through deception and killed by strangulation, sometimes accompanied by drowning. Following each murder, Nilsen performed a ritual in which he bathed and dressed the victim's body, which he retained for extended periods, before dissecting and disposing of the remains by burning them in a bonfire or flushing them down a toilet.
Nilsen became known as the Muswell Hill Murderer, as he committed his later murders in the Muswell Hill district of North London. He died at York Hospital on 12 May 2018 of a pulmonary embolism and a retroperitoneal haemorrhage, which occurred following surgery to repair an abdominal aortic aneurysm.
Early life Childhood Dennis Andrew Nilsen was born on 23 November 1945 in Fraserburgh, Aberdeenshire, the second of three children born to Elizabeth Duthie Whyte and Olav Magnus Moksheim (who had adopted the surname Nilsen). Moksheim was a Norwegian soldier who had travelled to Scotland in 1940 as part of the Free Norwegian Forces following the German invasion of Norway. After a brief courtship, he married Whyte in May 1942, and the newlyweds moved into her parents' residence.
The marriage between Nilsen's parents was difficult. 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. After the birth of her third child, Nilsen's mother concluded she had "rushed into marriage without thinking". The couple divorced in 1948. All three of the couple's children – Olav Jr., Dennis and Sylvia – were conceived on their father's brief visits to their mother's household. Her parents, Andrew and Lily (née Duthie) Whyte, who had never approved of their daughter's choice of husband, were supportive of their daughter following her divorce and considerate of their grandchildren.
Nilsen was a quiet yet adventurous child. His earliest memories were of family picnics in the Scottish countryside with his mother and siblings, of his grandparents' pious lifestyle (which he later described as "cold and dour"), and of being taken on long country walks carried on the shoulders of his maternal grandfather, to whom he was particularly close. Olav Jr. and Sylvia occasionally accompanied Nilsen and his grandfather on these walks. Despite being only five years old, Nilsen vividly recalled these walks as being "very long ... along the harbour, across the wide stretch of beach, up to the sand dunes, which rise thirty feet behind the beach ... and on to Inverallochy". He later described this stage of his childhood as one of contentment and his grandfather of being his "great hero and protector", adding that whenever his grandfather (who was a fisherman) was at sea "life would be empty [for me] until he returned."
By 1951 Nilsen's grandfather's health was in decline but he continued to work. On 31 October 1951, while fishing in the North Sea, he died of a heart attack at the age of 62. His body was brought ashore and returned to the Whyte family home prior to burial. In what Nilsen later described as his most vivid childhood recollection, his mother, weeping, asked him whether he wanted to see his grandfather. When he replied that he did, he was taken into the room, where his grandfather lay in an open coffin. As Nilsen gazed upon the body, his mother told him his grandfather was sleeping, adding that he had "gone to a better place".
In the years following the death of his grandfather Nilsen became more quiet and withdrawn, often standing alone at the harbour watching the herring boats. At home he seldom participated in family activities and retreated from any attempts by adult family members to demonstrate affection towards him. Nilsen grew to resent what he saw as the unfair amount of attention his mother, grandmother and, later, stepfather displayed towards his older brother and younger sister. Nilsen envied Olav Jr.'s popularity. He often talked to or played games with his younger sister Sylvia, to whom he was closer than any other family member following his grandfather's death.
On one of his solo excursions to the beach at Inverallochy, in 1954 or 1955, Nilsen became submerged beneath the water and was almost dragged out to sea. He initially panicked, flailing his arms and shouting. As he "gasped for air which wasn't there", he recalled believing that his grandfather was about to arrive and pull him out before experiencing a sense of tranquillity. His life was saved by another youth, who dragged him ashore. Shortly after this incident, Nilsen's mother moved out of his grandparents' home and into a flat with her three children. She later married a builder named Andrew Scott, with whom she had four more children in as many years. Although Nilsen initially resented his stepfather (whom he viewed as an unfair disciplinarian) he gradually gained grudging respect for him. The family moved to Strichen in 1955.
At the onset of puberty Nilsen realised he was homosexual, which initially confused and shamed him. He kept his sexuality hidden from his family and his few friends. Because many of the boys to whom he was attracted had facial features similar to those of his younger sister, Sylvia, on more than one occasion he sexually fondled her as she slept, believing that his attraction towards boys might be a manifestation of the care he felt for her. Nilsen made no efforts to seek sexual contact with any of the peers to whom he was attracted, although he later said he had been fondled by an older youth and did not find the experience unpleasant. On one occasion he also caressed and fondled the body of his older brother as he slept. As a result of this, Olav Jr. began to suspect his brother was gay and regularly belittled him in public – referring to him as "hen" (Scottish slang for "girl"). Nilsen initially believed that his fondling of his sister may have been evidence that he was bisexual.
As Nilsen progressed into adolescence he found life in Strichen increasingly stifling, with limited entertainment amenities or career opportunities. He respected his parents' efforts to provide and care for their children but began to resent the fact that his family was poorer than most of his peers, with his mother and stepfather making no effort to better their lifestyles; therefore Nilsen seldom invited his friends to the family home. At the age of 14 he joined the Army Cadet Force, viewing the British Army as a potential avenue for escaping his rural origins.
Army service Nilsen's scholastic record was above average. He displayed a flair for history and art but shunned sports. He finished his schooling in 1961 and briefly worked in a canning factory as he considered which career path he should choose. After three weeks at the factory, Nilsen informed his mother that he intended to join the army and receive training as a chef. 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. Within weeks, Nilsen began to excel in his army duties; he later described his three years of training at Aldershot as "the happiest of my life". 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.
While stationed at Aldershot, Nilsen's latent feelings began to stir, but he kept his sexual orientation well hidden from his colleagues. Nilsen never showered in the company of his fellow soldiers for fear of developing an erection in their presence; instead opting to bathe alone in the bathroom, which also afforded him the privacy to masturbate without discovery.
In mid-1964, Nilsen passed his initial catering exam and was officially assigned to the 1st Battalion of the Royal Fusiliers in Osnabrück, West Germany, where he served as a private. In this deployment, Nilsen began drinking heavily. He described himself and his colleagues as a "hard-working, boozy lot"; his colleagues recalled he often drank to excess in order to ease his shyness. On one occasion, Nilsen and a German youth drank themselves into a stupor. When Nilsen awoke, he found himself on the floor of the German youth's flat. No sexual activity had occurred, but this incident fuelled Nilsen's sexual fantasies, which initially involved his sexual partner – invariably a young, slender male – being completely passive. These fantasies gradually evolved into his partner being unconscious or dead. On several occasions, Nilsen also made tentative efforts to have his own prone body sexually interfered with by one of his colleagues. In these instances, whenever he and his colleagues drank to excess, Nilsen would pretend he was inebriated in the hope one of his colleagues would make sexual use of his supposedly unconscious body.
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. In 1967, he was deployed to the State of Aden (formerly Aden Colony, now part of Yemen), where he again served as a cook at the Al Mansoura Prison. This posting was more dangerous than his previous postings in West Germany or Norway, and Nilsen later recalled his regiment losing several men, often in ambushes en route to the army barracks. Nilsen himself was kidnapped by an Arab taxi driver, who beat him unconscious and placed him in the boot of his car. Upon being dragged out of the boot, Nilsen grabbed a jack handle and knocked the taxi driver to the ground before beating him unconscious. He then locked the man in the boot of the taxi.
Unlike his previous postings, Nilsen had his own room while stationed in Aden. This afforded him the privacy to masturbate without discovery. His developed fantasies of sex with an unresistant or deceased partner unfulfilled, Nilsen compensated by imagining sexual encounters with an unconscious body as he masturbated while looking at his own prone, nude body in a mirror. On one occasion, Nilsen discovered that, by using a free-standing mirror, he could create an effect whereby if positioning the mirror so his head was out of view, he could visualise himself engaged in a sexual act with another man. To Nilsen, this ruse created the ideal circumstance in which he could visually "split" his personality: in these masturbatory fantasies, Nilsen alternately envisaged himself as being both the domineering and the passive partner. These fantasies gradually evolved to incorporate his own near-death experience with the Arab taxi driver, the dead bodies he had seen in Aden, and imagery within a 19th-century oil painting entitled The Raft of the Medusa, which depicts an old man holding the limp, nude body of a dead youth as he sits aside the dismembered body of another young male. 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.