John (John Abraham) is an assassin working for a mobster named Captain (Bharat Dabholkar). After a hit went wrong, resulting in him killing an entire family(inluding a little girl), he is overcome with the guilt of his actions and decides to quit his job. He starts life anew with his pregnant wife Shalini (Priyanka Chopra) a bar singer.
Meanwhile, John's boss, Captain, is facing a threat from a rival don, Yunus (Vishwajeet Pradhan). After being attacked, Captain decides to teach the city a lesson by killing the city's top industrialist, top film producer, the cop backing Yunus and Yunus himself; so that everyone else falls in line and no one dreams of becoming another Yunus.
He decides that John must carry out this plan of his. To achieve this, he takes Shalini hostage. John is given 36 hours to kill the five targets on the hitlist. Things get worse when the city's toughest cop Wagh (Shiney Ahuja) traces him. John is pressed for time and the body count is growing.