Sathyamoorthy (played by Ramki) is an honest investigative journalist. He is killed for publishing the truth. Before dying, he tells his son Mathimaaran (played by Dhanush) that honesty and cleverness are equally important. While Sathyamoorthy is killed, his wife dies in the hospital after giving birth to a baby girl named Shweta (played by Smruthi Venkat). As expected, Mathimaaran is raising his sister.

When he grows up to become a journalist like his father, it affects his sister as well. Mathimaaran reveals politician Pazhani's (played by Samuthirakani) plan to win the election by changing EVM machines. Mathimaaran reveals the truth and gets into trouble. One day, a shocking incident turns his life upside down.