Plot

In the 1970s, Om, an aspiring actor, is murdered, but is immediately reincarnated into the present day. He attempts to discover the mystery of his demise and find Shanti, the love of his previous life.

Om Prakash Makhija is a Junior Artist in the 1970s Hindi film industry and in love with actress Shantipriya. Om rescues Shanti from an out-of-control fire scene and they become friends. His hopes seem to be coming true--until he finds out that she's married to film producer Mukesh Mehra and expecting his child. He then watches in horror as Mukesh, after luring her into an abandoned studio, sets it afire to prevent a financial loss and protect his career. Om attempts--unsuccessfully--to rescue her and eventually dies himself. 30 years later, Om has been reincarnated as the only son of Bollywood actor Rajesh Kapoor, and is himself an actor. His memories start to return when he meets his widowed mother Bela, from his previous life. He also meets Mukesh and they decide to make a movie, 'Om Shanti Om'. Om hires a look-alike of Shantipriya and hopes to force a confession from Mukesh, but things go awry and Om finds his life endangered once again.—rAjOo (gunwanti@hotmail.com)

Bollywood junior artiste Om Prakash Makhija hopes to make it big in life and is infatuated with popular starlet Shantipriya. But alas!--Shanti is to marry film producer Mukesh Mehra and is already pregnant by him. This crushes Om's hope of uniting with Shanti, but he is forced to rescue her when Mukesh lures her into an enstrangled position, resulting in the death of both. 30 years later Om is re-born to yesteryear Bollywood actor Rajesh Kapoor and is himself an actor. He meets with Mukesh and together they attempt to make a film 'Om Shanti Om'. Here Om will reunite with his beloved Shanti and start to regain his memory, which forces him to investigate--endangering his life once again.—gavin (racktoo@hotmail.com)

Junior artist Om Makhija dreams of becoming a big star and is in love with top actress Shantipriya. He spends most of his time in film studios with his friend Pappu, and they have had small roles in some big films. During a shoot Om saves Shantipriya and they become friends, and Om tries to express his love to her. Later he hears Shantipriya and producer Mukesh Mehra talking about their secret marriage and is devastated. Mukesh decides to shelve his film as Shantipriya is pregnant, but kills her instead. Om witnesses the murder before he too dies. Years later he is reborn as Superstar OK and recollects his past life when he comes across Mukesh--now known as Mike--and decides to work on a film with him. During auditions he meets Sandy, a Shantipriya lookalike, and with her and Pappu he plans to have Mukesh confess to Shantipriya's murder.—alex.mjacko@gmail.com

Om Prakash Makhija is a junior artist who dreams of becoming a hero overnight; his mother Bela inspires and encourages him to become a success. He gets to meet Shanti Priya one day and finds out that she is very popular, after a few misunderstandings, Om finally falls in love with Shanti, but is unable to express it to her. He gets to attend her first film, Dreamy Girl, by masquerading as actor Manoj Kumar. He also saves her in a filming episode from an uncontrollable fire and both became good friends. Om asks her out on a date and she agrees. Om is ecstatic and plans a wonderful evening for her, using props and a film set and several backgrounds in a studio to woo her, and she finally attends but under the pretext of a friend. The following day, Om tries to talk to Shanti on the sets of a film but she looks very preoccupied. He follows her into a makeup room and overhears her arguing with top producer Mukesh Mehra, and learns that she is married to him and expecting his child. Shocked and heartbroken, Om flees. One night, he notices Mukesh escorting Shanti to the set. He sees it catch fire and realizes that Shanti is trapped inside. Om tries to save Shanti, but is trapped and severely beaten by Mukesh's guard.—gavin (gunmasterM@hotmail.com)

Om Prakash Makhija (Shah Rukh Khan) is a junior artist in the 1970s Bollywood film industry, and in love with film star Shanti Priya (Deepika Padukone). Om fantasizes himself as a big-name superstar in the future. He lives with his widowed mother, Bela (Kirron Kher), and his friend Pappu Master in a small Chawl. Pappu is also a junior artist and hangs around studios with Om for work. They both run into a struggling actor Govinda Ahuja and suggest that he should change his name to Govinda, for success. Both Om and Pappu believe that he will never become a hero with the name Makhija, but Bela would have none of it.

One evening, Om views the premiere of Shanti's film Dreamy Girl, posing as Manoj Kumar (as Manoj's premier tickets were pick pocketed by Pappu). They are eventually chased out of the theatre when the real Manoj Kumar turns up to the premier. Later that night, Om becomes drunk and describes his vision of himself as a famous, wealthy film star (living in the house of superstar Rajesh Kapoor) to his friend Pappu (Shreyas Talpade) and some local children. Om pretends to have won an award.

Omi and Pappu land minor roles at R.C. Studios, owned by the egotistical producer Mukesh Mehra, who also launched Shanti's career. Lately, there is a noticeable friction between Mukesh and Shanti, and she refuses to give her shots unless the Producer (in her case Mukesh) is also on sets. The staff believes that Mukesh has not paid Shanti, which is why she is throwing a tantrum, but Omi believes that Shanti is not like that.

At the shooting of one of Mukesh's film, Om rescues Shanti from a fire scene where the fire has escaped control, and they become friends. Although Omi initially lies about being a Tamil film star to impress her, he eventually confesses the truth. Shanti genuinely likes him, and with Pappu's help, they share a memorable evening together. But then on, Shanti starts to ignore Om and Om cannot understand this sudden change in Shanti's behavior. He starts to pursue her.

One day, after following Shanti, he overhears her and producer Mukesh Mehra's (Arjun Rampal) conversation, that Mukesh and Shanti have married in secret. Shanti is furious when she learns that Mukesh plans to marry the daughter of the Harsh Mittal as he stands to inherit his vast studio as dowry. Mukesh is in the process of producing his most expensive film yet, which is titled Om Shanti Om and Harsh has invested Rs 40 Lakhs in the project. Mukesh says that the day Shanti reveals she is married, her career as an actress will be over. She reveals to Mukesh that she is pregnant with his child and expects a traditional wedding, which seems to please him. Heartbroken, Omi avoids Shanti.

Mukesh pretends to be happy with the news and invites Shanti at the set of their soon-to-be-made film Om Shanti Om. Mukesh promises to cancel the film, reveal their marriage to the public, and have a grand wedding on the set; but instead traps Shanti on the set and sets it on fire to prevent his financial loss (by returning Mittal's Rs 40 Lakhs) and downfall of his career. He lights up set on fire and locks Shanti inside. Mukesh leaves the set after that.

Om, who happens to be at the same location that night, attempts to rescue Shanti, but is attacked by Mukesh's guards, and later thrown from the building by an explosion. Outside, Om is hit by a car owned by Rajesh Kapoor (Javed Sheikh), a well-known actor taking his wife Lovely to the hospital to give birth.

At the hospital Om succumbs to his injuries, while Lovely gives birth to a son, also named Om Kapoor. Due to Rajesh's status as a superstar and to avoid any controversy, Rajesh's secretary bribes the doctor to classify Om's death as an accident. Thirty years later, Om Kapoor aka O. K., now a successful yet arrogant actor, and a lookalike of Om, nicknamed 'O.K.', and lives the luxurious life imagined by Om Prakash. Om also has a birthmark of "Ohm" on his right hand, exactly where Omi had an Ohm tattoo. Anwar (Nitesh Pandey) is Om's assistant. OK suffers from Pyrophobia and frequently encounters Bela, who believes him to be her son. He dismisses her as delusional. Pappu, now old, tries to explain the truth, but Bela remains unconvinced.

While shooting at the abandoned R.C. Studios for his superhero film, O.K. experiences vivid flashbacks. In acceptance of an award for best actor, O.K. unexpectedly delivers Om Prakash's drunken speech to the assembly. Pappu hears this on television and realizes Omi has been reincarnated. At a celebration of his award, O.K. is introduced by his father to Mukesh Mehra, now known as Mike, and thereupon completely recovers Om Prakash's memories. He later reunites with Bela and Pappu and conspires to avenge Shanti's death by making Mukesh confess his crime.

O.K. resumes filming Om Shanti Om at the old studio after convincing Mukesh to revive the project, and hires Sandhya "Sandy" Bansal, an aspiring actress who is a doppelganger of Shanti and a huge fan-girl of Om. He initially hides his plan but later reveals the truth to Sandy, who promises to help him. At the film's inauguration, Bela, disguised as a witch, tries to scare Mukesh, but the plan fails. However, despite a plan gone wrong, a photograph of Shanti inexplicably catches fire, unsettling Mukesh.

During a masquerade ball for the film's music launch, Om indirectly hints at Mukesh's guilt through Shanti's story. Sandy accidentally reveals her ruse by injuring herself, proving she is not a ghost. Mukesh, suspicious of the film reels, chases Sandy but is knocked out by a chandelier. When he regains consciousness, O.K. confronts him about Shanti's murder. Mukesh mocks O.K., claiming there is no proof.

Sandy then appears, disclosing that Mukesh had buried Shanti alive under the chandelier after discovering she had survived the initial fire. Both Om and Mukesh seem perturbed, since neither feels she would have known Shanti's tragic story this deeply; in the confrontation that follows, Om finally overcomes his Pyrophobia and defeats Mukesh, who is crushed to death by Sandy looking at the chandelier.

O.K. remains confused about Sandy knowing the truth about Shanti's death until Pappu and Anwar arrive with the real Sandy. He finally realizes that the woman with him is actually Shanti's ghost, who was also responsible for the unexplained aids in his plan. With her death now avenged, Om and Shanti bid each other a tearful goodbye, and he reunites with Sandy while Shanti runs up the stairs and disappears, having attained peace.