Magizh Thirumeni’s Thadam is a whodunit thriller with ample engaging moments, thanks to its gripping screenplay. Kavin (Arun Vijay) is a petty thief who indulges in various financial dealings with the help of his aide Suruli (Yogi Babu). A selfish person, he doesn’t value Ananthi’s (Smruthi Venkat) true love for him. Meanwhile, Ezhil (Arun Vijay in another role), who is into construction business, dreams of settling down with Deepika (Tanya Hope).
One of them murders a youngster, which becomes a sensational case. The police, under the guidance of Gopalakrishnan (FEFSI Vijayan), nabs Ezhil first based on his image, which is found on the deceased person’s phone. The police officer, who had been waiting for a chance to take revenge on Ezhil for a personal reason, plots to get him maximum punishment. However, he gets the shock of his life when other cops takes Kavin also to the custody.