Om Prakash Makhija is a Junior Artiste in Bollywood, who is infatuated with actress Shantipriya, and hopes to marry her someday. His hopes come to reality when he rescues her from a fire and they go on a date. Shortly thereafter he finds out that she is married to a film producer, Mukesh Mehra, and is expecting his child. He then watches in horror as Mukesh, after luring her in an abandoned studio, sets it afire. Om attempts to rescue her in vain, and he eventually is killed. 30 years later, Om is reborn as the only son of yesteryear Bollywood actor, Rajesh Kapoor, and is himself an actor. His memories start to return when he meets with his widowed mother, Bela, from his previous birth. He also meets with Mukesh and together they decide to make a movie Om Shanti Om . Om then hires a look-alike of Shantipriya, and hopes to force a confession out of Mukesh - but things go awry and Om finds his life endangered once again.

Farhan Qureshi and Raju Rastogi want to reunite with their fellow collegian, Rancho, after faking a stroke abroad an Air India plane, and excusing himself from his wife trouser less respectively. Enroute, they encounter another student, Chatur Ramalingam, now a successful businessman, who reminds them of a bet they had undertaken 10 years ago. The trio, while recollecting hilarious antics, including their runins with the Dean of Delhis Imperial College of Engineering, Viru Sahastrabudhe, race to locate Rancho, at his last known address little knowing the secret that was kept from them all this time.

Susanna is dark, magical, evil to some and mysteriously charming to the others. She also harbors a secret, known only to her and her faithful companions. Will her ever lasting quest for love ever come to an end?