Look-alike twins Prem and Arun Kumar live a middle-class lifestyle. When they grow up, Prem decides to be celibate, becomes a Catholic Priest, and re-locates to a small village, while Arun becomes a Police Officer in the region. Years later Prem is a well-respected Priest, while Arun is the Superintendent of Police. One day Prem visits Arun with regard to the incident of a young woman named Mary who had reportedly killed herself. He asks Arun to have the body exhumed in order to perform a postmortem. Arun suspends the Police Inspector who had Mary's body buried without following proper procedure, and goes to the graveyard to have the body prepared for a postmortem. When the coffin is dug up and opened Arun gets a shock when he finds that the dead person in it is Prem. He immediately begins an investigation (Tahqiqaat) to find out who killed Prem, and what happened to Mary's body. As the investigation continues, hampered by lies and deceptions by the village folks, he will find out that Prem appeared to have been leading a double life, and may have responsible for Mary's pregnancy and subsequent suicide.