Scientist Dr. Sanjay Mehra, has created a computer from which he sends variations of the syllable om into space, hoping to attract extraterrestrial life. When he believes he has finally received a response, the scientific community mocks him. While driving home, an alien spacecraft appears overhead. Distracted, Sanjay drives off the road, causing the car to explode, killing him. His pregnant wife Sonia, survives with injuries and from Canada, returns to her home, to India. When her son Rohit is born, he is mentally disabled due to an injury he received in the accident as a fetus. Sonia learns that although surgery is the only solution to Rohit's disability, but it could result in paralysis or death. Not wanting to lose her only remaining relation and sign of her husband, she raises him in the town of Kasauli, where he grows up to be a man of limited intellect.

Nisha Malhotra, a young lady comes to Kasauli and is initially antagonistic to Rohit due to his childish pranks against her. This causes her friend, who is the son of the collector of the town, Harbans Saxena, Raj, and his four buddies to attack Rohit and break his kick scooter, but Sonia chastises Nisha and Raj for assaulting Rohit, signalling them that Rohit didn't intentionally make fun of her or wanted to hurt her. Realizing her mistake, Nisha gifts Rohit a bicycle and also introduces him to her mother and father, who are also sympathetic to him.

Rohit and Nisha, now good friends, find Sanjay's old 'Om' computer and Rohit inadvertently summons the aliens. The visiting aliens leave in haste, accidentally leaving one from their group behind. Rohit, Nisha, Rohit's six young friends and Sonia find and befriend the alien naming him Jadoo (Magic) and discover his psychokinetic abilities. Raj does not like Nisha getting too much close to Rohit so bullies him and spreads a fake rumour that he and Nisha are getting married. This upsets Nisha and Rohit, who is especially hurt as he was under the impression that Nisha was his girlfriend.

Jadoo discovers that Rohit is mentally abnormal, and also gets to know that the reason behind his weakness & his father's death was the spaceship and uses his powers, derived from sunlight, to enhance Rohit's mental & intellectual ability. The next morning, Rohit finds himself with a clear vision; he later solves a 10th standard mathematics problem orally, despite being from 7th standard, surprising his mathematics teacher and even his catholic school principal. He later lectures his computer teacher for insulting him and to understand the responsibilities of being a teacher. As a result, Rohit finds himself accepted by most of the school.

Rohit's physical abilities are also increased to superhuman levels. Later, Raj and his buddies challenge Rohit and his friends to a basketball match. Rohit uses his new physique to score several baskets during the match so Raj and his buddies begin to play dirty to win the game. After the sun comes out, Jadoo helps Rohit and his young friends to win the game. The now changed Rohit meets Nisha and her parents and confesses his love for her, which Nisha now reciprocates.

Raj's buddies later corner Rohit's friends over their supernatural performance at the basketball game. Rohit's friends are forced to flee and Jadoo accidentally falls from their grasp. Constable Chelaram Sukhwani, sees Jadoo in the bag and quickly calls and informs the other policemen. The policemen, led by Inspector Khurshid Khan, come and capture the bag, although Rohit arrives in time to rescue Jadoo. He is later confronted by Raj and his buddies. Rohit, now infuriated, easily takes down Raj and his buddies, but not before the policemen catch up to him. It is then revealed that Jadoo is not in the bag and had escaped when Constable Sukhwani was busy calling and talking to the policemen.

However, Inspector Khan is suspicious of Rohit and confronts him at his house with his group. The policemen take Jadoo and knock Rohit out. When he regains consciousness, Rohit uses his super-speed to catch up to the police cars and arrives just in time to save Jadoo from being taken to America. The spaceship, which he had summoned with his father's computer beforehand, arrives back and Rohit bids a sad farewell to Jadoo. As Jadoo leaves, Rohit loses his superpowers and reverts to his disabled self. This saves him from the prosecution by the Government of India who felicitate him for his actions.

Later, Raj and his buddies return to harass Rohit and challenge him to kick a ball to them. An enraged Rohit kicks the ball into the bully's face as Jadoo returns Rohit's superpowers permanently. Rohit and Nisha thank Jadoo and get married.