Arrambam (2013)

Arjun is a brilliant, easy-going software engineer whose life changes the day a stranger named Ashok, working with a cool and capable woman called Maya, blackmails him into using his hacking skills. Ashok seems to be planting bombs and breaking into the accounts of powerful people, and the police soon start hunting all three of them. Bit by bit a flashback reveals who Ashok really is and why he has declared war on a group of men in high places, a story that ties back to the deaths of honest policemen and a friend he could not save. Arrambam was Ajith's second film with director Vishnuvardhan after Billa, and its slick style, stunts and Yuvan Shankar Raja's score made it one of the biggest Tamil hits of 2013. Rana Daggubati appears in a key supporting role, and much of the action was shot on location in Mumbai.