Raj (Shahid Kapoor) & Priya (Kareena Kapoor) just meet each other after both of their dreams have been shattered. They find an infant & realize that he has been dumped there by someone. They take pity on him, but after seeing a missing persons ad, they realize that the baby is the only son of Sonia Chang, a millionairess in Goa. The ad says that they will get a lot of money if they return the son back. They both need the money so they decide to return the baby to her, Sonia lives in a huge mansion, with Mr. & Mrs.Lobo (Dinyaar Contractor & Roshan Tirandaaz), her servants. She is discussing the change in her will with her lawyer Mr.Dixit (Vivek Vaswani), when the duo inform her about her baby.
Sonia is overjoyed to learn this & calls them to Goa. Meanwhile, her casino is hosting some interesting people. One of them is Natwar (Paresh Rawal), a notorious gambler who has come along with his wife Gracy (Payal Rohatgi). Natwar has pawned his hotels to Sonia & has only one hotel left in his posssession. When he loses money, he is forced to pawn the last hotel too. He keeps this a secret, but Gracy knows the fact. Another person is KK (Johnny Lever) who has come along with his wife Ruby (Tanaaz Currim). There is also a playboy named Rocky (Upen Patel) among them, who is a big hit with ladies, even Sonia.
Raj & Priya come to Goa, where they run into a drunkard (Raj Zutshi), who is loitering near the mansion. The drunkard runs away on seeing them. The duo are surprised to see the mansion to be in dark, since they expected Sonia to be waiting for them. They enter the mansion & call for Sonia. When she doesn't answer, they realize that something is wrong. On seeing the state of the house, they realize that Sonia has been robbed, but are later horrified to see Sonia dead. The duo run, but with police on heels, Raj tells Priya to run away. Karan who is the cheaf inspector suspects Raj and arrests him, but doesn't reveal a thing about Priya. Priya comes to rescue Raj & soon the duo become prime suspects.
To shield the other person, both Raj & Priya lie. Karan starts interrogating other people and realizes that almost everybody has a shaky alibi. Soon everybody starts lying for one reason or other. Nevertheless, this results in everybody's lie falling apart. Karan is able to reconstruct what actually happened that night. Based on Mr.Dixit's statement about the will & everybody's statement, Karan is able to find the truth. First, he procures the drunkard, whom Raj & Priya believe to be the murderer. But, Karan goes on to explain that he is in fact, the kidnapper.
Karan goes on to explain that the kidnapper was hired by someone to kidnap the baby & leave it somewhere it won't be found. The masterminds thought that Sonia will be forced to change her will, but when the baby was rediscovered, they knew that Sonia had to be killed before being united with her baby. Hence, they murdered her, while other people incriminated themselves by fooling others to believe that it was robbery gone wrong. Based on the testimonies, Karan points out that only two persons had the motive: Mr. & Mrs.Lobo. He catches their lie too & arrests them. Everybody else is exonerated, while Raj & Priya decide to marry & adopt the baby.