Copycat crimes are criminal acts that are inspired or even directly modelled after something reported over news networks, or featured in fictional media. The term has its origins from back in 1916, when it was used to describe crimes that were influenced by the legacy of Jack the Ripper. It soon became clear that large-scale media coverage could have a strong influence on how criminals committed their crimes. With the prevalence of popular media such as television shows, movies and video games, copycat crimes have become a sensitive issue. Studies have generally shown that the specifics of popular media don't cause people to become criminals, but they can give ideas on what crimes are committed, and how. In the worst cases, mass murderers have been found to aim for a higher number of victims in order to beat the 'high scores' set by previous criminals reported in the news. Movie villains are often the most popular fictional characters to be impersonated by criminals, with copycat crimes linked to famous villains like Tyler Durden from Fight Club and Ghostface from the Scream series. In recent years, the most common antagonist to have inspired criminals in high-profile crimes is the Joker. The version of the character seen in Nolan's The Dark Knight film has particularly attracted criminals, presumably thanks to the character's anarchic values and striking appearance. This list takes a look at nine real crimes that were inspired by Gotham City's Clown Prince of Crime. From highly destructive acts of arson to some of the most horrifying mass murders in history, the crimes seen in these entries are truly chilling.