Ghamasaan is an action drama set in the rugged region of Bundelkhand, Uttar Pradesh. The story revolves around Maharaj (Arshad Warsi), a feared dacoit who rules the forests with his armed gang and terrorizes the local population. With influential police officers and politicians allegedly in his pocket, no one dares to challenge his reign of terror. However, pressure mounts on the government when opposition leader Kumari Sarojini (Seema Azmi) raises her voice against Maharaj's atrocities. To contain the growing political crisis, the authorities deploy Aditya Singh (Pratik Gandhi), an honest officer from Lucknow, along with a team of STF personnel, to Maharaj's stronghold. Aditya is instructed to curb Maharaj's activities and ensure that the upcoming elections are conducted peacefully, with the expectation that he and his team will withdraw once the polls are over. But Aditya has other plans. Determined to put an end to Maharaj's reign once and for all, he launches a dangerous operation against the dreaded dacoit. What happens next forms the rest of the film.