The Wanda Beach Murders, also known simply as "Wanda", were the unsolved murders of Marianne Schmidt and Christine Sharrock at Wanda Beach near Cronulla in Sydney, New South Wales, Australia, on 11 January 1965. The victims, both aged 15, were best friends and neighbours from the suburb of West Ryde, and their partially buried bodies were discovered the next day. The brutal nature of the slayings and the fact that they occurred on a deserted, windswept beach brought massive publicity to the case. By April 1966, police had interviewed some 7,000 people, making it the largest investigation in Australian history. It remains one of the most infamous unsolved Australian murder cases of the 1960s, and New South Wales' oldest unsolved homicide case.

Christopher Bernard Wilder, also known as the Beauty Queen Killer and the Snapshot Killer, was an Australian-American serial killer who abducted at least twelve young women and girls, killing eight of them during a six-week, cross-country crime spree in the United States in early 1984. Wilder's series of murders began in Florida on February 26, 1984, and continued across the country through Texas, Oklahoma, Colorado, Nevada and California, with attempted abductions in Washington and New York. Wilder victimized attractive young women, most of whom he would entice by promising to take their pictures. After subduing them, he would torture and rape them before shooting, stabbing with a knife, or strangling them to death. Two or more of his victims were electrocuted using a makeshift electrical cord.