Sri Badrinatha Moorthy aka "Badri" is a happy-go-lucky youth who spends his days roaming around with his friends Azhagu, Howrah, and Joot, ogling girls and repeatedly failing his exams. His father, Viswanathan, a cafe owner, is disgusted with his irresponsibility and constantly chides him. His older brother Vetri, who is a college-level kickboxer and Viswanathan's favourite son, on the other hand, dotes on him. Janaki, aka "Jaanu", who is Badri's neighbour and childhood friend, is in love with him, but the feeling is one-sided as Badri mainly considers her as a source of money and cars; Badri constantly borrows large amounts of money from Jaanu as well as expensive cars from her father's garage to impress girls.

One day, Badri meets Mamathi, who is a rich college girl, and poses as a wealthy industrialist's son in order to impress and love her. Mamathi falls for Badri's lies and soon expresses her love to him. But when she finds out the truth, she breaks up with him and insults him in front of Viswanathan. When Viswanathan further finds out that Badri has taken large amounts of money from Jaanu, he kicks out Badri, tired of his antics.

Badri, who is now homeless, finds support from Jaanu, who advises him to be more responsible and redeem himself in Viswanathan's eyes. He realises the love Jaanu has for him and begins to reform himself. Meanwhile, Vetri is attacked and seriously injured by his kickboxing arch-rival Rohit, who happens to be Mamathi's new boyfriend and Badri's enemy as well, thus ruling him out for the final match of the inter-collegiate kickboxing championship against Rohit. Badri decides to fight for Vetri by taking his place in the final and trains hard for it. Finally he defeats Rohit in the final, thus winning the kickboxing championship. He dedicates the trophy to Vetri, reconciles with Viswanathan, and reciprocates Jaanu's love.