Writer: Bunty Rathore
Mithun Chakraborty as Pritam “Pappu” Singh Ghai
Ajay Devgn as Gopal “Gopu” Kumar Santoshi
Arshad Warsi as Madhav Singh Ghai
Tusshar Kapoor as Lucky Singh Ghai
Kunal Khemu as Laxman Singh Ghai
Shreyas Talpade as Laxman Santoshi
Kareena Kapoor as Daboo
Ratna Pathak Shah as Geeta “Guddi” Patnaik/Geeta Santoshi/Geeta Ghai
Johny Lever as Pappi
Mukesh Tiwari as Vasooli
Ashwini Kalsekar as Chintu
Sanjay Mishra as Dagga/Babli
Vrajesh Hirjee as Teja/Nandu
Murali Sharma as Inspector Dhande
Vijay Patkar as Constable Gandhaari
Prem Chopra as Prem Chopra (special appearance)
Viju Khote as Shambu Kaka (special appearance)
The story follows Pritam (Mithun Chakraborty), an elderly bus driver. His three good-for-nothing sons, Madhav (Arshad Warsi) the group leader; Laxman (Kunal Khemu) the poetic idiot; and Lucky (Tushar Kapoor) the innocent mute are always up to trouble, mostly by scamming people. On the other hand, Geeta (Ratna Pathak) is an elderly woman, whose two sons, Laxman (Shreyas Talpade) the stammerer; and Gopal (Ajay Devgn) the strong but kind leader; own a water sports stall at the beach. Gopal and Laxman’s partner is Daboo (Kareena Kapoor) on whom Gopal has a crush, but never shows it.
Three robbers Pappi (Johny Lever), Daga (Sanjai Mishra) and Teja (Vrajesh Hirjee) rob the queen’s necklace and are on the run from police and end up in Goa. Pappi, the don, who suffers from short-term memory loss, hides the necklace in Pritam’s house. Soon enough, Pritam’s sons open a water sports shack opposite Geeta’s sons’ stall, and a rivalry begins. Filled with mayhem, both the groups try to take down each other’s business but fail hilariously. In response to this, Pritam goes to meet Geeta, (although he doesn’t know that they are Geeta’s sons) to sort this rivalry out and it turns out that Pritam and Geeta were college-lovers. Daboo overhears their love story, and decides to get the two married, without their sons’ permissions.
After the marriage, the two families start living in one house, filled with non-stop laughs and mayhem. It is also revealed to the five sons that they are not Pritam and Geeta’s sons but orphans after overheard by Lucky. Although they vow not to tell them that they know that they are orphans and to hide that, they become friendly like brothers. They also open a big shop of toys aided by Vasooli Bhai (who is another not-so-don don) and Pappi for money. Pappi eventually remembers where he hid the necklace, and turns himself in along with his goons Daga and Teja. After the long squabble, chase and mayhem, Gopal and Daboo manage to trick Pappi to take out information of hidden necklace and thus Pritam finds it and gets Pappi and his goons arrested. The film ends with Pritam and Geeta going out for honeymoon and Gopal, Madhav, Lucky and the two Laxmans end up brawling after an argument.
During argument Daboo tries to stop them but they don’t.The film end with Daboo pulling the director of the film Rohit Shetty and other crew members to stop their argument. The whole cast and crew to stop them together, which itself creates chaos.