The film begins with Shalini (Priyanka Chopra) narrating how much she loved John (John Abraham) despite of knowing he was a contract killer and how things might have been different had he not picked up a gun. The film goes into flashback mode and John is shown to be an assassin working for a mobster named Captain (Bharat Dabholkar). Accompanied by two friends Kaif (Murali Sharma) and Bull (Rajesh Khera), he is assigned a hit, which he carries out, but also ends up killing an entire family, who arrives untimely to the house from where the hit was planned. Apart from the adults, one of their daughters gets shot unintentionally by John. He gets traumatized and despite his friends telling him to move on, he becomes guilt-ridden and explains everything to Shalini, with whom he plans to escape away. The city's toughest cop, Wagh (Shiney Ahuja), starts investigating the murder and in the process, comes close to the surviving daughter of the deceased family.