On 1 January 2011, a sudden bomb blast occurs in London, killing several people. The scene shifts to the same place after exactly a year, where a blind man Kenny Thomas (Vikram) lays flowers on the memorial and mourns someone\\\'s death during the bomb blast. He is then given some secret details by a mysterious woman. Kenny then takes a taxi driven by Satyan (Santhanam) who is a comical Tamil guy. He drops Kenny at a place and waits for him to return. But Kenny actually goes inside to kill someone. He kills him and throws him down. Seeing the corpse, Satyan flees. During this entire scene, Kenny is shown to produce a sound from his mouth, to find his way, which is later shown as echolocation. Later Kenny is shown to play piano in a local church, and he is blind he has so many people who care for him. In the meantime, Kenny carries out two more murders, taking the same taxi driven by the innocent Satyan, following instructions from the mysterious woman.
Sarah Vinayagam (Amy Jackson), a British-born Indian girl, wins the Miss London title, and to build her social profile, she goes to Kenny\\\'s church and acts like helping out there. Initially Kenny does not like her, but eventually they become friends. Sara\\\'s father is a doctor, who supports Kenny as he is blind. Police officer Veerakathi (Nasser), a Eela Tamil, is the officer in charge of the murders. As the autopsy of the murdered victims take place under Sara\\\'s father, Veerakathi visits him and comes to know about Kenny, who is admitted there for a small accident. Verrakathi initially suspects Kenny, but is not convinced that he is the murderer. As Satyan is found on all the murder spots, the police arrest him, suspecting that he must be having a connection with the murders. But Satyan manages to find a picture of Kenny from a local newspaper and informs Veerakathi. Satyan is released and he meets Sara, and both of them go to a place (which she comes to know from Kenny\\\'s phone, which he misses during a fight with the local thugs). They reach there in time to see Kenny almost kill a guy named Victor (a steel company owner). But Kenny flees the scene after seeing them and takes Satyan\\\'s taxi to escape. As he is blind, he runs the taxi into a river along with Satyan and Sara. Later they are shown to be in a river bank shocked. Sara and Satyan try to escape, where they see Geetha (Lakshmi Rai), who confronts Sara and Satyan, and reveals the real identity of Kenny.
Kenny is actually a RAW agent in India, whose real name is Shivakumar. He, along with Sharath (Jagapati Babu), complete various missions for the Indian government. Siva and Sarath are very close friends. Meantime Siva gets married to Meenakshi (Anushka Shetty), who is an Eye Doctor in Delhi. They both have same views on marriage that, one should first meet someone and then become friends and then fall in love and then get married. But as their marriage happens in a hurry, they decide that, they must first become friends. As time goes by, they become closer to each other and almost become the complete pair. Meenakshi decides to express her love to Shiva on the New year\\\'s Day (which turns out to be His birthday).
In the Meantime, Sharath handles a case where an Indian Army secret (a flowchart) about a WMD goes missing. Shiva shows interest in this case and he goes to London (on a different name,where a former Indian Policeman named Kenny helps him) to find an important clue, as Sharath is injured during a fight. But Shiva is shocked to find his plan go terribly wrong and is now chased by the London police, following a few incidents. But now he finds a shocking truth about Sarath. It is shown that Sharath is the mastermind behind the missing Flowchart and he sells it to a terrorist group, with some help from the London militants. Shiva finds this entire plot and asks Sharath to surrender. But he later learns that Meenakshi also has come to London along with Sharath (to surprise Shiva on his Birthday and Propose to him). So to save her, Shiva abides by Sharath\\\'s order and he comes to a place (with Kenny), where a sudden bomb blast occurs, killing Kenny and Meenakshi and Blinding Shiva. The actual wife of Kenny is Geetha, who decides to take revenge on those responsible for the death of Kenny and Meenakshi. She forms a team with Shiva, and joins him in a School where he learns Echolocation from Daniel Kish an expert echolocator. After that, Geetha tells the people who caused the disaster to Kenny and kills them when Mr. Veerakathi finally understood why Kenny was killing them. After electrocuting Sharath in Victor\\\'s (Sharath\\\'s friend) factory, the Union Minister requested Kenny to come back to India as Shivakumar but however, he rejects the request as Kenny\\\'s former identity as Shivakumar had \\\'died\\\' and he is going to spend his life for Meenakshi.