One of the most respected inspectors, Arjun Joglekar (Mukesh Khanna) is killed by drug dealer and gangster Goli (Shakti Kapoor). Mona (Shilpa Shetty), a cabaret singer and Goli's mistress, agrees to testify against Goli and is placed into witness protection by Inspector Karan (Akshay Kumar), Arjun's younger brother, who aims to fight any injustice and avenge his brother's murder. When Goli finds out about Mona's forthcoming testimonial which would expose his real identity, he tracks her down and kills her.
Deepak Kumar (Saif Ali Khan), who is the most romantic actor around, is frustrated with his roles and being type-caste as a romantic hero. He would like to do something different and bring some change and excitement to his dull and boring existence. One day to overcome his tedious life, he gets drunk and drives around, is arrested by the duplicate police, and brought to his rowdy producer. This is where he meets Karan and is very impressed with his assertiveness, courage, and honesty; Deepak would like to study his behavior so that he can use this as a background for his next movie.
Karan meets Basanti who is an identical duplicate of Mona. He promises to let Deepak hang around him if Deepak can get Basanti to pose as Mona. Deepak trains Basanti and presents the new "Mona" to Karan. Karan places Basanti at the Moonlight Hotel as an amnesiac Mona, where she can report on Goli's criminal activities. That's how they uncover Goli eventually. While Karan and Mona fall in love with each other, Deepak falls is love with Karan's sister, Shivangi.