John [John Abraham] is an assassin who works for mob boss Captain [Bharat Dabholkar].

One fateful day, John ends up massacring an entire family. As he stares into the eyes of the little girl, whose life is slowly ebbing away from her, realization hits John and he decides to quit and start life afresh, sans bloodshed, with his wife Shalini [Priyanka Chopra].

Captain is facing a major threat from a rival don Yunus [Vishwajeet Pradhan] and after an attack on his life, he decides to retaliate. Captain wants to kill the city's top industrialist, top film producer, the cop backing Yunus and lastly, Yunus himself. His strategy: Set a precedent so that everyone else toes the line and no one dreams of becoming another Yunus.

But to execute this plan, Captain needs the help of his ace assassin - John. One man who can make this audacious plan work, but he is one man who has sworn never to pick up his gun again.

Captain takes John's love, his wife, away from him and holds her hostage; in return, he has to kill the five targets in the next 36 hours. From this point on, John plots, double crosses and triple crosses everyone. Friends turn foes and the body count begins to grow.

On John's trail is Mumbai's tough cop Wagh [Shiney Ahuja]. In a game of cat and mouse, John tries to fight the forces of nature and cut loose from the masters of puppets.