Died Naturally Custody Killers

David Parker Ray became one of the most infamous serial offenders in American history after constructing a soundproof torture chamber inside a trailer on his property in Truth or Consequences, New Mexico. Known as the "Toy-Box Killer," Ray was convicted of kidnapping, torture, and sexual offences against multiple women. Although investigators suspected he murdered numerous victims over several decades, no homicide convictions were ever secured because no bodies were recovered. His crimes remain among the most disturbing criminal investigations in modern American history.

Dennis Andrew Nilsen became one of the United Kingdom's most infamous serial killers after murdering at least 15 young men and boys in London between 1978 and 1983. Often referred to as the "Muswell Hill Murderer," Nilsen lured vulnerable victims to his home before strangling them and keeping their bodies for extended periods. His crimes were uncovered only after human remains blocked drains at his apartment building, leading to one of Britain's most shocking homicide investigations.

Donald McMillan Jr. murdered 62-year-old Helen Fiona Torbet in the Scottish Highlands in July 1993 after developing an obsession with her during her regular stays at his parents' guesthouse near Inverinate. After killing Torbet, McMillan concealed her body in the grounds of the property and maintained for months that she had left with another man. A lengthy missing-person investigation eventually focused on McMillan, who directed police to the burial site. He was convicted of murder in 1994 and sentenced to life imprisonment, later receiving a 15-year punishment part. McMillan remained imprisoned until his death in 2007.

Edward Theodore Gein became one of the most infamous killers in American history after murdering two women and exhuming numerous bodies from local cemeteries near Plainfield, Wisconsin, during the 1950s. Although convicted of only two murders, the disturbing discoveries inside his farmhouse—including items fashioned from human remains—made Gein a cultural phenomenon whose crimes inspired characters such as Norman Bates, Leatherface, and Buffalo Bill. His case remains one of the most extensively studied in criminal psychology.

George Emil Banks became one of the most infamous mass killers in Pennsylvania history after murdering 13 people during a shooting spree in Wilkes-Barre on September 25, 1982. Among his victims were five of his own children, their mothers, and several relatives. The murders shocked the United States because of the extraordinary number of family members killed in a single attack. After decades of legal proceedings centred on his mental competency, Banks died in prison in 2024 without ever being executed.

Herbert William Mullin became one of California's most infamous serial killers after murdering 13 people in and around Santa Cruz between October 1972 and February 1973. Mullin later claimed he believed the killings were necessary to prevent catastrophic earthquakes, a delusion linked to severe mental illness. His short but deadly murder spree ended with his arrest in February 1973, and his case remains one of the most widely studied examples of psychosis and serial homicide in the United States.

Ian Duncan Stewart Brady became one of the United Kingdom's most infamous serial killers after carrying out the Moors Murders with Myra Hindley between 1963 and 1965. The pair murdered five children and concealed several victims on Saddleworth Moor, creating one of the most notorious criminal cases in British history. Regarded as the dominant figure in the partnership, Brady spent the remainder of his life imprisoned and became a symbol of extreme criminality in the United Kingdom.

Ivan Milat was an Australian serial killer responsible for the murders of multiple backpackers in New South Wales between 1989 and 1992. His crimes became one of the most notorious cases in Australian criminal history. Milat targeted travellers and used deception to gain their trust before carrying out violent attacks. He was later convicted and sentenced to life imprisonment without parole, remaining incarcerated until his death in 2019.