Shiva and Vishnu are identical twins. Shiva, the elder one, is a bus conductor, while Vishnu, the younger one, has a mild intellectual disability. During their childhood, Shiva overhears his parents' plot to send Vishnu to an unknown orphanage and to hide this information from him. To save his brother Vishnu, Shiva runs away to another city with him and strives hard to look after him. A 'dada' Sundaramoorthy, who runs a beggar trade, beats Vishnu brutally, and Vishnu becomes disabled for life. Shiva leaves Vishnu in a home run by a social worker Lalitha. During the day, Shiva works as a bus conductor, and at the same time, poses as Vishnu: to play Robin Hood and steal from the rich and corrupt. A gang including Thangam, Mani, and others assist him in these operations. He is never suspected, and so, with the stolen money, he takes care of not only Vishnu, but also 800 people in other institutions for the physically disabled. A college student Lavanya falls in love with Shiva, but he later learns that she is Sundaramoorthy's sister-in-law. Matters worsen when Sundaramoorthy becomes the chairman of the institute for the physically disabled. How Shiva deals with the situation forms the rest of the story. Meanwhile, Thangam is secretly in love with Shiva, though he does not know this. Later she gives up her love and lets Lavanya marry Shiva. At last, Shiva marries Lavanya and Thangam marries Vishnu. The brothers live happily ever after.