On 20th July 1969, Derek Percy approached 12-year-old Yvonne Tuohy and her friend Shane Spiller whilst they were playing at their local beach in Warneet, Victoria. He snatched Yvonne into his car before trying to get Shane too, but Shane managed to defend himself. Percy took Yvonne to a remote location where he then murdered her. Shane contacted the police and was able to recall several things about Percy’s car, including a navy sticker which led police to the local Navy base HMS Cerberus and to Percy. After his arrest Percy admitted to the crime and calmly led police to Yvonne’s body. Controversially, Percy was found ‘not guilty’ on reasons of insanity but was considered too dangerous to ever be released. Since then, Percy has been a suspect in a number of murders and disappearances of other children all over Australia including 7-year-old Linda Stilwell who went missing from St Kilda beach in 1968. He was known as Australia’s most notorious child killer until his death in prison in July 2013. (thetvdb.com)