Ram Dayal, a simpleton is strangled to death by Diwan Rai Bahadur, a tyrant on the eve of Diwali. This is seen by Bhagyavanti, Ram Dayal's wife and eldest son Kalu.
Bhagyavanti and her three children leave the village and on their way get separated due to a train accident. Bhagyavanti and Raja are given shelter by Inspector Kapoor, who is a widower and Father of only daughter Asha.
Kalu and Guddi are brought up by Dindayal, a shady character. Years roll by, Raja becomes Police Inspector and is in love with Ahsa, the only daughter of Inspector Kapoor. Kalu, renamed as Ranga is Dindayal's hireling. Ranga in his process of wrong doings has an altercation with Shyam due to which Shyam rapes Guddi. Guddi commits suicide.
Ranga kills Shyam for ruining his sister's life and run away from law in his process of escape from law he hands into a gang of dacoits and eventually becomes their thief. Titli, a girl in the dacoit's gang is silently in love with Ranga, but Ranga whose only aim is to kill Diwan Rai Bahadur, murderer of his father. Ranga becomes a ferocious dacoit and is a terror in Shamgadh. The Police institutes a reward on Ranga's head. Raja voluntarily gets himself transferred to Shamgadh to arrest Ranga.
Whether Inspector Raja arrests Ranga ?
Whether Ranga knows that Inspector Raja is his younger brother ?
Whether Ranga is able to take the revenge of his father's killer ?
Whether the separated family of Dindayal re-unites ?
For all plausible answers to above questions, see Yogesh Arts International's "RANGAA AUR RAJA".
(From the official press booklet)