Happy Mehra is a free-spirited middle-class girl. Rocky Khosla is a playboy and an arrogant goon. Happy constantly butts head with Rocky. On the other hand, Rocky's kind-hearted elder brother Chintu falls in love with Happy and befriends her. She and Chintu get married as she learns about his feelings. However, he dies in an accident.
Chintu and Rocky's father, Kulwant, blames Rocky for the accident and disowns him. Rocky sets up a hotel to fulfill Chintu's dream. Happy joins him and they slowly become friends. Ranvijay Shroff, a famous lawyer fighting for righteousness of society, starts falling for Happy. Rocky is falsely accused of molesting Happy's sister, Smiley, and jailed for ten years.
Three years later, Happy is running the hotel successfully and has a solid friendship with Ranvijay. After escaping prison, Rocky is jealous of Happy and Ranvijay's bond and proves his innocence. He realises his feelings for Happy and decides to confess. However, Ranvijay is obsessed with Happy, so he kills his brother Ranveer and his girlfriend Anaya. Happy starts believing that everyone she knows is dying because of her, and that they will be safer without her in their life. Happy fakes her death to leave the city and to send Ranvijay to jail. Rocky is heartbroken.
Six years later, Happy is a RJ, known as Khushi (which is the Hindi word for "Happy"). Rocky has a wife, Harleen, whom he dislikes and is still mourning Happy. Harleen hates their son, Honey, as she never wanted a child. Honey runs away and meets Happy, who looks after him. She finds out about him being Rocky's son. Rocky learns that Happy is alive. Kumar tries to shoot Honey. Harleen comes in between to save him and dies. Happy proposes to Rocky and they get married.
