"Mr Cruel" is an Australian serial child rapist who attacked three girls in the northern and eastern suburbs of Melbourne, Victoria, in the late 1980s and early 1990s. He is also the prime suspect in the 1991 abduction and murder of a fourth girl, Karmein Chan. His moniker came from a newspaper headline in The Sun.
Mr. Cruel has never been identified, and his three confirmed attacks and the suspected murder remain unsolved cold cases. There is a reward of A$200,000 for the two abductions. In April 2016, twenty-five years after the death of Karmein Chan, Victoria Police increased the reward for information that leads to the perpetrator's arrest and conviction, from A$100,000 to A$1,000,000.