Hand-in-hand, Hollywood’s glamour couple of Sean Penn and Charlize Theron set off flashbulbs aplenty at the L.A. premiere of “The Gunman”. Starring Penn, the film is based on novel “The Prone Gunman”, as an international operative who wants to leave his past behind him in order to obtain a peaceful life with is longtime love. “The Gunman” opens in the U.K. and Ireland on the 20th March.