The small village of Ramgarh is home to ex-policeman Thakur Baldev Singh (Sanjeev Kumar). The film begins with Thakur summoning an old colleague and requesting him to track down a pair of small-time thieves he once apprehended in the line of duty. Though the two petty criminals Veeru (Dharmendra) and Jai (Amitabh Bachchan) are notorious, Thakur feels that they would be the ideal men to help him end the tyranny of Gabbar Singh (Amjad Khan), an infamous dacoit (bandit) wanted by the authorities for a Rs 50,000 reward. After scenes showing how the three fought together during a train robbery attempt, and how the criminals often get in and out of jail, Veeru and Jai are found and brought to Ramgarh. They are told by Thakur that they are to bring Gabbar to him alive for Rs 20,000, plus the Rs 50,000 reward.
Three of Gabbar's enforcers arrive in Ramgarh to collect supplies from the defenseless villagers, but they go back empty-handed due to Veeru and Jai's intervention. In Gabbar's camp, the tyrant interrogates the three about why they were defeated by only two men. His psychotic nature is shown when he subjects his men to a twisted version of Russian roulette, but eventually shoots the three men dead.