31 December 2010: At 11:59 pm, a sudden bomb blast occurs in London, killing several people.

After a year, A blind man named Kenny Thomas lays flowers on the memorial and mourns someone's death during the bomb blast. He is provided with secret details by a mysterious woman. Kenny takes a taxi driven by Sathyan, a comical Tamilian. Kenny kills someone and throws the body down. Sathyan flees. Kenny produces a sound from his mouth to find his way, which is later explained as echolocation. Kenny plays the piano in a church. He is blind and has so many people who care for him. Soon he carries out two more murders, taking the same taxi driven by the innocent Sathyan and following instructions from the mysterious woman. Inspector Veerakathi, a British Tamil officer is in charge of investigating the murders.

Sara Vinayagam, a British-born Anglo-Indian woman, wins the Miss London title, and to build her social profile, goes to Kenny's church. Initially, Kenny is aloof but eventually, they become friends. Sara's father is the doctor performing autopsies of the dead bodies. Veerakathi starts to suspect Kenny. As Sathyan is found on all the murder spots, the police arrest him, suspecting he has a connection with the murders. Sathyan finds a picture of Kenny in a local newspaper and informs Veerakathi of Kenny's connection.

Sathyan is released and meets Sara. Kenny who is about to kill the steel company owner named Victor, flees the scene after sensing their presence. He takes Sathyan's taxi to escape. Sara and Sathyan join him in pursuit. As he is blind, Kenny runs the taxi into a river. Taking refuge on a riverbank, Kenny's identity is revealed by the mysterious woman.

Kenny is a RAW officer from India, whose real name is Shivakumar and he marries Meenakshi, an eye doctor in Delhi. While handling a case where an Indian Army secret (a flowchart) about a WMD goes missing, Shiva has come to London. Things go radically wrong and he ends up becoming Kenny after the London bomb blast. The mysterious woman is the real Kenny's wife Geetha, who is taking revenge on those responsible for bomb blast in which Kenny is killed.

What happens thereafter forms the movie's climax.