The film begins with a scene of a police station where Sasi, the police officer in charge, orders that the documented criminal cases in the form of manuscripts be converted into digital format. During this process, he comes across a really spine-chilling dacoity murder case from several years ago. After reading the case history, he calls up the police officer who had taken charge of the case, Theeran Thirumaran.
The story shifts to the year 1995, where Theeran is in his police training college undergoing training to be posted as DSP from TNPSC exams. He tops the training period. Simultaneously, in a house along the highway of Tamil Nadu, a group of dacoits wrecks the house by barging in, killing all the people inside gruesomely and taking the belongings.
Meanwhile, Theeran returns to his hometown of Tanjavur, falls in love with his new neighbor Sripriya aka Priya, and marries her. Later, Theeran becomes known in the police department for his ways of handling various cases, and he is later moved to Ponneri after a dacoital attack. Police Inspector Satya and Theeran both handle the case but lead nowhere with the case. Therefore, in 2003, Theeran, Sathya, and a group of other police officers go around India to see if they are able to identify the fingerprints of the dacoits. During this process, Theeran learns that these dacoits are actually tribe members of the left over cultural groups after the Indian Independence. They are eventually stopped by the carelessness of their superior officers, and the case is put on hold.