The film opens with a renegade sniper Craig (Vikranth) who assassinates an army officer from a long distance and is given a new assignment by a traitor to finish off an ISRO scientist named Abdul Kamaal (the reference to APJ is not missed) within thirty days. The story then shifts to Kambam where a PT teacher Thulasi Raman (Sathyaraj) leads a peaceful life with his son Sethu (Udayanidhi Stalin) wife and a daughter. Sethu, who works as a librarian to retired Colonel Mathews (Rajesh) meets a kleptomaniac Nandhini (Amy Jackson) who steals books from the library and after a few altercations the two fall in love. Vikranth for some unknown reasons lands in the hill town and is seen wandering and taking photographs of Rajesh. Meanwhile Sathyaraj complaints about a political based bar owner Kandhan (Mime Gopi) and in an ensuing fight Uday comes to his rescue bashing up the goons. Mysteriously the corpse of Kandhan is pulled out of a water falls and in his hands a ring belonging to Sathyaraj is found. The police arrest Sathyaraj and Uday takes it upon himself to clear his fathers name and sets out to find the real killer.