Amitabh Bachchan as Don appeared in a double role in this action film. In the film, there is this 'Don' Amitabh who is a ruthless smuggler. His only soft spot is Zeenat Aman. 'Don' dies in a police confrontation, and as a co-incidence there is his look-alike a country bumpkin, who has come to a city for the first time and breaks into 'Yeh hai bambai nagariya tu dekh babua'.
Cop Iftekhar spots the duplicate Amitabh and sends him as 'Don' to the notorious gang that is now being monitored by Pran. Zeenat comes to know the difference but she has already fallen in love with Don Duplicate. She joins him and Iftekhar in the guerilla warfare against Pran and his accomplices.