Meet Rahul (Tusshar) and Karan (Riteish). Not exactly diaper buddies, but definitely thick friends. Though Rahul is sincere simple and hardworking and Karan is just the opposite. However, they share one thing in common. Both are intelligent but Kool wannabes. Although both hail from well to do families, the drive to make it on their own steam has led them to the city of dreams… Mumbai. While Rahul aspires to become a famous fashion designer some day, Karan dreams of marrying a girl with a pretty face and a prettier bank balance.

Meanwhile, the city is rocked with a series of rape & killings & the police are in search of this dreaded Serial Killer. Things take a funny turn, when Rahul becomes the prime suspect as the serial killer and this sets the police on the trail. They hatch a plan with the help of a famous criminologist (Anupam Kher) to nab him in action.

The job of nabbing Rahul in action is entrusted to a violent lady Inspector called Urmila Martodkar (Ishaa Koppikar). Urmila enters Rahuls life on some pretext, and tries to seduce him into showing his true face of a rapist and a killer.

Meanwhile Karan, the wannabe Casanova, has managed to woo his boss's ex-girlfirend called Kiran. Kiran’s parents strike a plan to brainwash Kiran from letting go of Karan and for that they Kiran’s cousin Rekha (Neha Dhupia), a psychologist for help.

A complete laugh riot and a thorough entertainer, the film reaches its crescendo when the police are on the verge of arresting Rahul as the rapist and Karan is about to wed Kiran at the temple….

What Happens Next? Do the Mistaken Identities fall into place? Is the Police able to nab the REAL Killer?