Pasupathy (Shiva) is a go lucky guy who wanders without any purpose. He is living with his younger sister Kavitha (Monisha) and house maid Senthamarai (Kovai Sarala) who is a part-time liquor seller in black market. Pasupathy's sister is in love with his close friend Mano (Soori) which Pasupathy is not aware. His friend indirectly tries to convey that matter to him to which he does not understand. Pasupathy has a maternal uncle (Ilavarasu) who is a lawyer and their care taker since their parents died. Pasupathy loses his house to a bank on a surety crisis which involved his father. Hence he is compelled to settle in job. Pasupathy's uncle applies for an opening in his friend's mineral water company 'Classique' for marketing head post. He gives many instructions about the owner Sivagurunathan (Prakash Raj) who is an ardent devotee of Lord Murugan and who is against recommendations. Pasupathy manages to get job by dressing in a simple Gandhian manner, faking as a Murugan devotee and tells he follows very valuable principles written in the book of Sivagurnathan himself which attracts Sivagurunathan.
Pasupathy one day lies to his boss that his mother got injured and leaves to watch IPL match.

There he enjoys a lot with his friends by drinking, screaming, cheering etc. which unexpectedly is seen by Sivagurunathan as he was present on his friend's invite for a business purpose. Sivagurunathan is furious on Pasupathy's behavior and he captures his activities in his mobile. Next day he issues termination order to Pasupathy. To secure his job Pasupathy lies that Sivagurunathan has actually seen his identical twin brother Ganguly Kandhan who is a Karate master. The difference between the both of them is that, his brother has blue eyes unlike his. Sivagurunathan believes him half minded and yet gives him his job again.

Sivagurunathan has a daughter Janani (Isha Talwar) who learns everything half baked. Her interest turns to learning self-defense skills and tells her father to appoint a master to teach Karate. Sivagurunathan calls Pasupathy to send his brother for Karate coaching. Pasupathy wears blue contact lens and visits his home and manages to make Sivagurunathan to believe he is Ganguly Kandhan. Pasupathy and Janani had already met where Pasupathy rushes to save Janani from fire but he is rescued by Janani from fire. Pasupathy is attracted to Janani and he impresses both Janani and her maternal grandmother (Sachu).

Sivagurunathan meets a bank officer (Devadarshini) who actually took Pasupathy's house. She tells him that Pasupathy is actually a fraud and she has not met anyone like Ganguly Kandhan which confuses Sivagurunathan. He appoints a CID to follow Pasupathy and find out if he has a brother Ganguly Kandhan. Pasupathy manages to cheat the CID and make him believe that there are two brothers.

But he innocently behaves and submits his and Kandhan's resignation letter to him telling that his mother did not want them to work for a boss who doubts their loyalty. Sivagurunathan says that he would apologize for his doubtful behavior to his mother which creates further trouble for Pasupathy. He rushes home and disguises his servant maid Senthamarai to act as his mother. Sivagurunathan believes that setup and apologizes to Pasupathy's mother.

Janani falls for Ganguly Kandhan and she wants him to find if he loves her and she keeps him a test. She wants him to wish for her birthday on the following Tuesday and she will not tell him that she is going to Dubai.

Pasupathy tries to get information from Janani's grand mother. He goes to Sivagurunthan and tells Kandhan has gone to Dubai which furies Sivagurunathan as he doubts that Kandhan has gone to impress his daughter. Pasupathy pretends to say that he will go to Dubai and stop his brother and bring back his daughter to which Sivaguru accepts. Sivaguru plans to marry off his daughter to innocent Pasupathy against Janani's wishes. Pasupathy goes to Dubai and both propose their love.

Pasupathy's friend blackmails him to let him marry his sister otherwise he would tell his double act to Sivaguru. Pasupathy who had no other go arranges for their marriage. Janani comes out of home as she does not want to marry Pasupathy but only Kandhan but she finds that both are same and gets angry on him But he convinces her by saying all he did is for her sake which cools her.

Sivaguru misunderstands that Janani is going to marry Kandhan and rushes to stop it but finds that Kadhan is Pasupathy himself. He furiously chases him and Pasupathy runs. After several chases and runs Pasupathy manages to tie the knot but he does not do so as he did not want to marry Janani against his boss' wishes. Sivaguru changes his mind and let them marry.

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