Vijay Kumar (Vijay) is an honest and sincere DCP of Chennai. He takes up a case involving the rape and subsequent death of an IT employee Raji. He finds out that the rapist is Ashwin, the son of Labour Minister Vanamaamalai (J. Mahendran). Vijay kills Ashwin and reveals himself as the murderer to Vanamaamalai, who swears to take revenge on him for killing his son. Meanwhile, Vijay falls in love with a medical student Mithra (Samantha Ruth Prabhu) and both eventually get married and lead a happy life. But, Vijay's happiness is short-lived as Vanamaamalai, his younger brother Ratnam (Azhagam Perumal) and their henchmen barge into his house one night and kill Mithra and Vijay's mother (Raadhika). They even brutally assault Vijay and attempt to drown Vijay's baby daughter Niveditha aka Nivi in the bathtub. The dying Mithra manages to rescue Nivi and asks Vijay to take care of her, but not before making him promise that he will quit the police and be a peaceful and loving father to Nivi, following which she dies in Vijay's arms. Vijay fakes his death, changes his name to Joseph Kuruvilla, maintains a low profile and moves to Kerala with Nivi and his constable friend Rajendran (Rajendran) to protect Nivi from Vanamaamalai and his gang.