Guna is one of Kumbakonam's most powerful gangsters. Guna's younger sister, Nandini, is breathtakingly beautiful. Guna likes Nandini, but she is disgusted by her brother's rowdy behavior and decides to leave her house. Kathir, a boy who loves Nandini, is rejected because Nandini says she will never love anyone again because of her brother's rowdiness and cruelty. Despite her dislike for her brother Guna, Kathir wants Nandini to be with him. So he joins Guna and teaches him about values and humanity. Guna eventually changes his ways and surrenders to the police for the sake of his sister Nandini. Sangili Vathiyar, Guna's Guru, attempts to murder him, but Kathir gives his life to save Guna. What happens to Nandini? Do Guna and Nandini reunite?
