Ganga Aur Sura is an action movie. The storyline start with an Inspector Shekhar (Iftekhar) is an honest and upright officer of the Indian police force. Shekhar will sacrifice anything to catch the dreaded dacoit Vikram Singh (Kader Khan). Vikram has but one weakness – his young daughter and Shekhar had a young son. There is a violent exchange of children between the two opponents. Shekhar’s younger son Suraj is carried off by the dacoits and presumed dead by the police while the dacoit’s daughter is carried off by Ganga (Sunil Dutt), the inspector’s older son. Shekhar brings up Vikram's daughter as his own while Vikram makes Suraj (Shashi Kapoor) a dacoit. Now the children were grown up and the rivalry continues. The climax deals with how everyone comes to know the fact as who is whose children and it ends happily.