Thanedaar is an action drama. The movie follows the story of two estranged brothers - Avinash (Jeetendra) and Brijesh (Sanjay Dutt), who are separated when their father, Police Inspector Jagdish Chandra (Dalip Tahil), is killed by goons. Avinash is adopted by the Police Commissioner and becomes a Police officer, while Brijesh is taken by the goons and grows up and becomes a criminal. Years later, the two brothers meet and find themselves on the opposite sides of the law. Will the two be able to accept each other and unite to find the culprits who destroyed their family?