Diwan is a Tamil film from South India, released in 2003. The film stars Sarathkumar, Kiran, Vadivelu. It was directed by Surya Prakash, who previously directed Maayi with Sarathkumar. S. A. Rajkumar composed the music. Its Hindi dubbed version was released under the title "Mahabali". This film is a "Failure" at box office.
Raghavan (Sarathkumar) and Velu (Vadivelu) work as cooks in a non-veg hotel. Raghavan loves Geetha (Kiran) who is the daughter of a rich man (Vijayan), but her father is against this love and insults him as a poor man. Raghavan challenges that he will be rich in a year.
There is a subplot in the story, for Meenakshi (Sharmili), a daughter from a rich family; she is the apple of the eye of the family. Meenakshi ran home with her lover Raju, who worked as a driver to her house. He tells that his friend Dinesh will help them. However, Raju escaped because he saw a bad dream where he is killed by her family as if it will happen in reality. Due to that he vanishes. Raghavan understood her plight and helps her.
Suddenly he comes to a place where all call him as Duraisingam. Raghavan does not know who Duraisingam is. Manorama explains to him that Raghavan is the grandson of Duraisingam. The flashback is Duraisingam (Sarathkumar again) is a do-gooder who helps poor people, and he has a clash with Kaathavaraayan (Jaya Prakash Reddy), a big rowdy. Duraisingam could not kill him because he promised to his wife that she will never become a widow.
In the clash, Duraisingam's two sons are killed, and the baby (the son of Duraisinggam's older son) is lost. The baby happens to be Raghavan. Duraisingam surrenders himself to the police. After the flashback, Raghavan visits the jail only to know that Duraisingam had died a few years back.
Kaathavarayan kidnaps Raghavan and Meenakshi. Meenakshi's father and relatives bash Raghavan but leaves him after knowing the truth. Raghavan leaves Kathavarayan and says that he should live as a reformed man. Meenakshi marries the groom selected by her parents, and Raghavan unites with Geetha.