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 Sathyan (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, Sathyan 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 as 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 Sathyan, following instructions from the mysterious woman.
Sara 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 she is 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 British Tamil, is the officer in charge of the murders. As the autopsy of the murdered victims takes place under Sara's father, Veerakathi visits him and comes to know about Kenny, who is admitted there for a small accident. Veerakathi initially suspects Kenny but is not convinced that he is the murderer. As Sathyan is found on all the murder spots, the police arrest him, suspecting that he must be having a connection with the murders. But Sathyan manages to find a picture of Kenny from a local newspaper and informs Veerakathi. Sathyan 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 Sathyan's taxi to escape. As he is blind, he runs the taxi into a river along with Sathyan and Sara. Later they are shown to be in a river bank shocked. Sara and Sathyan try to escape, where they see Geetha (Lakshmi Rai), who confronts Sara and Sathyan 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. Shiva and Sarath are very close friends. Meantime Shiva gets married to Meenakshi (Anushka Shetty), who is an eye doctor in Delhi. They both have the same views on marriage that one should first meet someone, become friends, 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 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 (with 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 Sharath. It's 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 out about 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). 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.Daniel Jordan as Richard
UTV Motion Pictures commenced an innovative title contest in Twitter and it received massive response from Vikram fans. Vikram was revealed to play the role of a blind man, who practices the technique of human echolocation, the ability to detect objects, their position and size by sensing echoes. Vikram underwent special sessions with Daniel Kish, an internationally renowned expert of human echolocation. The team had planned to bring Kish to Chennai for the audio launch ceremony. Anushka Shetty was chosen to portray Vikram’s wife in the film. Amy Jackson plays a British-born-Tamil girl in the film and was said to dub for herself as well. Telugu actor Jagapati Babu was selected to play villain.
Filming commenced in Chennai in early December 2011 and was to be held in various locations in the US for 60 days and later in Delhi and various locations across southern Tamil Nadu. Sources said that the film would be entirely shot in Los Angeles city. Almost 50 per cent of the shoot was completed with the Delhi and Chennai schedules. While "delays in getting the visa for the entire cast and crew" was the official reason given for the change of location from the US to the UK, sources told that the move was also necessitated to keep the budget from skyrocketing. Some scenes were shot in UK. Lakshmi Rai joined the team in London in May 2012. A duet song between Vikram and Amy was shot on the River Thames.
The soundtrack album was composed by G. V. Prakash Kumar, featuring lyrics written by Na. Muthukumar. It is the 25th album of the music director.
Thaandavam was produced on a budget of ₹500 million (US$7.8 million). The film helped raise ₹2 million (US$31,000) for the National Association of Blind (NAB) through its premiere show donor passes. The film released about 1000+ screens worldwide. The satellite rights of the film were sold to STAR Vijay. The film was later dubbed and released in Telugu as Shiva Thaandavam on 5 October 2012, while in 2015, the film was released in Hindi under the title Desh Prem The Real Hero.
The Times of India rated the film 3/5, writing "Director Vijay and actor Vikram collaborate again in this movie after their earlier successful outing in Deiva Thirumagal, And Thaandavam'has everything going for it – big cast, good locations, a story with potential and a competent director – yet the result is far from satisfactory because of a weak and meandering screenplay, and poor pacing." Rediff's Pavithra Srinivasan wrote that the film was a "damp squib" and gave 2 out of 5 stars. Indiaglitz wrote: "Thaandavam has it's [sic] good sides and it's [sic] bad ones". Sify's reviewer claimed that it was "Vikram and him alone who diverts your attention from the film's little logical script flaws and spellbinds you with an endearing act that is Thaandavam's biggest strength". in.com's critic stated that it was a "neat revenge saga", further adding that it was "worth a watch for its neat screenplay and lavish production values", while giving it 3 out of 5. Prakash Upadhyaya of Oneindia.in gave 3/5 and wrote "Thaandavam is not glamorous but it is rich. It does not have masala elements yet it is entertaining". Tamilko wrote: "Thaandavam’s dreary screenplay hampers the much needed pace for a film set in espionage backdrop. Though Vikram greatly rescues the movie the dull and predictable sequences doesn’t help Thaandavam’s course". The Hindu described it as a fiery dance of the righteous.