This article contains spoilers for Netflix's The Murder of Rachel Nickell For years, the 1992 murder of mother Rachel Nickell, as she walked with her son on Wimbledon Common, remained unsolved. Robert Napper, suffering from paranoid schizophrenia, was found guilty of killing Samantha Bisset and her four-year-old daughter Jazmine in a vicious stabbing attack months afterward. However, no evidence existed linking him to Rachel's brutal murder.