Gunasingam, a family-loving farmer who hails from a small town, tries his best to keep his big family united despite him being misunderstood by many.

The story, set in the backdrop of Nallore, a small town in Thoothukudi District, revolves around Sub-Inspector Durai Singam, a brave and just policeman who serves in his hometown primarily to fulfill his father’s wish. Durai Singam settles every dispute in his town patiently with his words of wisdom and resorts to force only when the situation demands it. Kavya, a city girl who comes on vacation to Nallore, falls in love with Durai Singam. Erimalai, Durai Singam's bumbling colleague and friend, often accompanies him.

Picking up the storyline from where Singam ended, Duraisingam has gone undercover after meeting the Home Minister and is working as an NCC officer in a school in Thoothukudi. The only people who know about this operation are the Chief Minister and Home Minister apart from himself.

Simhachalam, a watchman is sentenced to death for stealing a precious diamond. However, a group of cowboys save Simhachalam and offer him the diamond, only on a condition that he fulfills a promise.