The story is about Sanjay Ramaswamy (Surya), a rich businessman and the events surrounding his relationship with Kalpana (Asin).

Kalpana, an advertisement model goes around telling her advertisement crew that she is the love interest of Sanjay. She does this in spite of she having never met him and also goes to the extent of giving an interview about her relationship to a popular magazine. Sanjay happens to hear about this through the media and wants to settle scores with her. On his way, he catches a fleeting glimpse of a young woman (who happens to be Kalpana) helping handicapped children to cross a street. It is love at first sight for Sanjay. He moves on to confront Kalpana at her advertisement studio. He is pleasantly surprised to realize that she is the same helpful woman he saw a while ago. He chooses to hide the fact from her that he is Sanjay. Kalpana eventually falls in love with him.

Once, while on a train to Mumbai, Kalpana saves a group of young girls from abuse by a group of goons. After a few days, the same goons come to Kalpana's house in order to avenge their embarrassment. Incidentally, Sanjay arrives at the scene and fights off the goons, but during the ensuing fight, Kalpana is murdered. The irony showcased is that Kalpana never finds out that he is Sanjay. The dacoits strike the downcast Sanjay on his head severely with a metal rod. Sanjay survives the blow, but suffers from a short-term amnesia. At any given time, he does not remember anything that happened more than 15 minutes back. He determines to take revenge on those responsible for Kalpana's death. The rest of the story is about how Sanjay goes about finding the goons despite his memory loss.