Pasupathy (Shiva) is a carefree man who is unemployed. He lives with his younger sister Kavitha (Monisha) and house maid Senthamarai (Kovai Sarala) who is a part-time black market liquor seller. Kavitha is in love with Pasupathy's close friend Mano (Soori) which Pasupathy is not aware of. Mano indirectly tries to convey that to him to which he does not understand. Pasupathy's maternal uncle (Ilavarasu) is a lawyer and their caretaker 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 a 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 Murugan and who is against recommendations. Pasupathy manages to get the job by dressing in a simple Gandhian manner, posing as a Murugan devotee and tells he follows very valuable principles written in the book of Sivagurunathan himself which attracts Sivagurunathan.

Pasupathy one day lies to his boss that his mother got injured and leaves to watch an IPL match. There he enjoys a lot with his friends by drinking, screaming, cheering, etc. which is seen by Sivagurunathan as he was present on his friend's invite for a business purpose. Sivagurunathan is furious on Pasupathy's behaviour and he captures his activities on mobile. The next day he issues termination order to Pasupathy. To secure his job, Pasupathy lies that Sivagurunathan has actually seen his identical twin brother GanguLee Kandhan, a karate master who has blue eyes unlike his. Sivagurunathan believes him half-heartedly 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 believe he is Gangulee. Pasupathy and Janani had already met when Pasupathy rushed to save Janani from fire, but Janani ended up saving him. 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 Gangulee which confuses Sivagurunathan. He appoints a CID officer to follow Pasupathy and find out if he has a brother GanguLee. Pasupathy manages to cheat the officer and make him believe that there are two brothers. But he innocently behaves and submits his and GanguLee'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 apologise for his doubtful behavior to his mother which creates further trouble for Pasupathy. He rushes home and disguises Senthamarai to act as his mother. Sivagurunathan believes that setup and apologises to Pasupathy's "mother".

Janani falls for GanguLee 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 grandmother. He goes to Sivagurunthan and tells Gangulee has gone to Dubai which angers Sivagurunathan as he doubts that GanguLee 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 Sivagurunathan accepts. Sivagurunathan plans to marry off his daughter to Pasupathy against Janani's wishes. Pasupathy goes to Dubai and both propose their love. Mano blackmails Pasupathy into letting him marry Kavitha otherwise he would reveal his double act to Sivagurunathan. Pasupathy, with no other option, arranges for their marriage. Janani leaves her home as she does not want to marry Pasupathy but GanguLee. But upon realising Pasupathy's fraud she angrily beats him. He convinces her by saying all he did is for her sake which cools her. Sivagurunathan misunderstands that Janani is going to marry Gangulee and rushes to stop it but finds that GanguLee is Pasupathy himself. He furiously chases him and Pasupathy runs. In the temple, he bumps into a man (Santhanam) who is being forced to marry a girl against his wishes. They concoct a plan to foll Sivagurunathan. After several chases and runs Pasupathy manages to get the chance to marry Janani, but declines as he does not want to marry Janani against his boss' wishes. Sivagurunathan changes his mind and lets them marry.