Masti is a film that has a story relating to the Bangalore Underworld.The story has a semblance of connection to the story of one person named as Masti, an underworld Don of the late sixties. Masti whose original name is Siddappaaji hails from Kollegal Thaluk and his brother Rachappaaji has migrated to Bangalore. Rachappaaji works as a social worker and is an envy of several politicians and rowdies. . Masti's brother gets killed in front of other family members in one of the functions in his area. An enraged Masti takes a sickle and kills one of the killers who is the brother of a corperator. He is arrested and with the help of some dons he gets released. Then he becomes a don by default. He saves a girl from being forcibly married. The girl starts loving him. Masti is in a dilemma whether to continue with his underworld activities or to respond to the love of the girl. Meanwhile, Masti's opponents are also trying to finish him off.