Artham (1989)

The movie starts with a loner named Ben Narendran writing a suicide note. He mentions that he is committing suicide as he has nothing to do with his life. He ends up saving another young man who has the same intention. Janardanan has committed a murder out of desperation and is scared of revenge. Narendran consoles him and offers him to take the blame of the murder so that Janardanan can live freely. Narendran gets sentenced to lifetime imprisonment. While in jail, he writes a book under the pen name "Ben" which becomes immensely popular. Once out of jail, Narendran gets word that Janardanan has died mysteriously. He sets out on a mission to find the culprits and destroy those who caused his death.