Two friends, Arjun Singh (Amitabh Bachchan) and Pyare Mohan (Govinda), are in the police force. Arjun's sister Seema (Raveena Tandon) is in love with Pyare. Arjun has no female companion and some petty comments are made about his age.
The villain Zorawar (Paresh Rawal) runs a business smuggling arms and diamonds, under a cover of being a statue maker. Zorawar appears terrified of the police, but the mood seems to come and go: When it comes to snuffing one out, he has no problem doing so. Once, in a hotel, he discovers that he is being spied upon and along with the cop spying on him, he also gets rid of an eyewitness, played by Divya Dutta (in a cameo role).
But there's another: Neha (Ramya Krishnan), a friend of the first eyewitness, who happens to see her friend die. Scared, and with the gangsters after her, she calls the police station and asks for Pyare, but since he is not there, Arjun is asked to go to her, and masquerade as Pyare, who had been described as a very good person to Neha by her dead friend.
In a considerable amount of confusion, he takes her to Pyare's house and even goes to the extent of asking Pyare to masquerade as Arjun Singh. As Arjun and Pyare exchange places and get busy trying to protect Neha, a hilarious riot starts when in pop two petty thieves who look exactly like Arjun and Pyare.. They call themselves Bade Miyan and Chote Miyan.
Arjun and Pyare are blamed for every crime the crooks commit and things aren't helped when Shyamlal (Anupam Kher), the police commissioner, is also thrashed by the doubles. Also, Arjun and Pyare are blamed for stealing a diamond from a bank and even messing up a security operation for Madhuri Dixit (herself, in a special appearance), all of these acts having been committed by Bade Miyan and Chote Miyan, masquerading as Arjun Singh and Pyare Mohan.
Matters are not helped when even Bade and Chote are mistaken for Arjun and Pyare by Seema and Neha, thus completing the confusion.Further trouble arrives when Zorawar kidnaps Seema and asks for the diamond and Neha in return. Arjun and Pyare, who have been arrested, are saved by the arrival of Bade Miyan and Chote Miyan, who explain their acts of theft and conning, and promise to get Neha and Seema back.
They then, along with the commissioner, stage a dance program at Zorawar's hideout. When Arjun and Pyare don't arrive on their call, they are asked to dance continuously at gunpoint by Zorawar and nearly pass out doing so, when Arjun and Pyare arrive and everyone at the hideout is arrested. The crooks leave after apologising to Neha and Seema for the confusion
However, some of Zorawar's men, hijack the police van which is to take Zorawar and his associates to jail. They are stopped on the way by Bade and Chote, asking for a lift. The latter realise who really are in the van and proceed to badly thrash Zorawar and his men and return him to jail. Arjun and Pyare are badly criticised for their mistake regarding the hijacking of the van and the two crooks are given a job in the police force by the commissioner himself.
The film ends with Arjun and Pyare ending up being demoted to the post of traffic police officers and Bade and Chote Miyan taking their place as police inspectors.