What would you do if you came across a murder? Walk away? Take a photo? Attack the assailant with a bouquet of flowers? Such were the responses of various onlookers in a prank to end all pranks. Viral marketing agency Thinkmodo, based in New York, was behind the stunt, which aimed to promote upcoming gangster film Dead Man Down, starring Colin Farrell. Quite a controversial move, but the idea quickly went viral, and gained coverage across the globe, including on the Mail Online and in The Telegraph.