Motivations - Compulsion

Randy Steven Kraft became one of America's most infamous serial killers after murdering at least 16 young men and boys across California, Oregon, and Michigan between 1972 and 1983. Often referred to as the "Scorecard Killer" because of a coded list discovered in his possession after his arrest, Kraft is suspected by investigators of murdering more than 60 victims. Convicted of 16 murders, he was sentenced to death in California, where he remains incarcerated.

Arthur John Shawcross became one of America's most infamous serial killers after murdering 14 people in New York between 1972 and 1989. After serving a prison sentence for killing two children, Shawcross was released on parole and later went on to murder at least 12 women in the Rochester area. His crimes remained unsolved for several years before investigators linked him to the murders through surveillance, witness testimony, and forensic evidence. Shawcross was sentenced to 250 years in prison, where he remained until his death in 2008.

Nikolas Jacob Cruz became one of the most notorious mass killers in modern American history after carrying out the February 14, 2018, shooting at Marjory Stoneman Douglas High School in Parkland, Florida. Armed with a semi-automatic rifle, Cruz murdered 17 students and staff members and wounded 17 others before fleeing the campus, making it one of the deadliest school shootings in United States history. The massacre shocked the world and sparked an unprecedented movement led by student survivors demanding stronger gun laws and improved school safety. Cruz's history of behavioral problems, mental health concerns, online threats, and numerous contacts with law enforcement became central to public debate following the attack. The shooting permanently changed the national conversation surrounding school violence and mass shootings.

Robert Clive Napper became one of the United Kingdom's most infamous serial killers after murdering Rachel Nickell in 1992 and Samantha Bisset and her four-year-old daughter, Jazmine, in 1993. Before his identification, Napper committed numerous violent sexual assaults across South East London, becoming known as the "Green Chain Rapist." Advances in DNA profiling eventually linked him to the murders after years of investigative failures, making his case one of Britain's most significant forensic breakthroughs.

Colin Ireland became one of the United Kingdom's most infamous serial killers after murdering five gay men in London over a seven-week period in 1993. Seeking notoriety, Ireland later admitted he deliberately set out to become a serial killer after reading an article suggesting Britain had none. Nicknamed the "Gay Slayer," he targeted men he met in London pubs before strangling them in their own homes. His brief but deadly murder spree shocked Britain and remains one of the country's most disturbing examples of predatory serial homicide.

Aaron Campbell became one of Scotland's most infamous child killers after abducting and murdering seven-year-old Megan Montgomery in Airdrie, North Lanarkshire, in 2020. Campbell lured the child from outside her home before killing her and concealing her body in nearby woodland. Following an extensive police investigation, he was convicted of murder and sentenced to life imprisonment with one of the longest minimum terms imposed in Scotland for the murder of a child.

Frederick Walter Stephen West became one of the United Kingdom's most infamous serial killers after murdering numerous young women and girls between the late 1960s and 1980s. Working both alone and with his wife, Rose West, he targeted vulnerable victims, many of whom disappeared after visiting the couple's home at 25 Cromwell Street in Gloucester. The discovery of multiple bodies buried beneath the property exposed one of Britain's most shocking serial murder cases and permanently cemented Fred West's place among the country's most reviled offenders.

Harold Frederick Shipman became one of the most prolific serial killers in modern history after murdering patients under his care while working as a general practitioner in England. Convicted of 15 murders in 2000, a subsequent public inquiry concluded he had likely killed at least 215 patients, with some estimates suggesting the true total exceeded 250. Shipman's abuse of trust, combined with the enormous scale of his crimes, fundamentally changed patient safety, death certification, and medical oversight throughout the United Kingdom.