Lakhan Singh "Lucky" (Sonu Sood) is the "king" of the Australian underworld, a position which he reaches after being jailed for a wrong offense, when some one keeps drugs in his bag, as soon as he reaches Australia. He takes the revenge after completing the jail term , by killing those involved, and eventually he reaches to the position of King, accompanied by his associates (played by Javed Jaffrey, Neha Dhupia, Sudhanshu Pandey). The high point of his journey is when he Happy Singh (Akshay Kumar) promises to bring Lakhan Singh back to his village. However his boarding pass gets mixed with someone else and then meets Sonia (Katrina Kaif) whom he starts loving but upon reaching his destination things take a precarious turn when a series of comic misadventures run him out of any money. He finds lucky's house and lucky tells him that he cannot come back to India leaving his buisness and throws him out. He is fortunate to find warmth and affection in a elderly lady (Kirron Kher) whom Happy treats like his mother. In a strange turn of events Lucky is saved from a life threatening attack by Happy risking his own life. In spite of this, Lucky is paralyzed and Happy becomes the new "King". The elderly lady comes back to him saying that her daughter is coming from India but doesn't know that she is poor. Happy gives her a consolidates her and gives her a home to find out that her daughter is Sonia and she is engaged to Puneet (Ranvir Shorey). Puneet comes to know that Happy is the king and tells Sonia whom upon hearing this gets disappointed because of her harted against criminals. Puneet hires Mika Singh (Javed Jaffrey) Lucky's brother who is hungry to become the "king" (the only thing stopping him is his partial blindness and deafness) to kill Happy. Mika tells one of his men to kill the paralyzed Lucky where as he will kill Happy at Punnet's and Sonia's wedding after he receives his specially ordered hearing and eyesight aid. When the hitman attempts to kill Lucky, Lucky snaps out of paralysis. At the wedding Mika's men attacked, the cowering Puneet runs away and leaves Sonia alone Mika's men try to grab her but Happy protects her and fights them at the end the preist unknowingly declares Happy and Sonia married. Happy tries to ask for forgiveness for this mistake but Sonia accepts him as her husband. while they are leaving Mika encounters them, now with his aid. Lucky then comes and shocks them all Happy tells Mika that being the "king" is no great thing Lucky always found sadness being the king, a true king doesn't fight for himself but for others he also tells that there is only one true king which is GOD. Mika then cries and hugs his brother. The credits scene shows that Happy brings Lucky back to India