Picking up the storyline from where Singam ended, Duraisingam (Suriya) 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. Sathya (Hansika Motwani) is a student who falls for Duraisingam though he is waiting to marry Kavya (Anushka Shetty), his love interest from the previous film. Susai (Santhanam), a local who works in the same school shows Duraisingam parts of Thoothukudi and also tells him about the rouge elements dominating the area helping him in his surveillance. He requests the Home Minister to transfer Erimalai (Vivek) and another cop for assisting him. Sathya?s moves are frequently repulsed by Duraisingam who learns that Sathya is the niece of Thangaraj (Rahman). Bhai (Mukesh Rishi) and Thangaraj, are two criminals who control the area. Bhai and Thangaraj have connections with an international gangster and drug lord Danny (Danny Sapani). Though they are partners in their smuggling business, they conceal their partnership to the outside world and pretend like arch rivals when they are out in the public. How Duraisingam overcomes the criminals, brings down their empire and finally unites with Kavya forms the crux of the story.