be a part of the remake, citing the film had already "gone down in history". Early indications suggested that Udhayanidhi Stalin had replaced him but the claims were false. In November 2010, reports emerged that Vinay Rai or Nakul were set to play the role, however Vinay cited that he refused the project as the role was not as meaty as the other two characters. Consequently, the production house signed Srikanth to play the role, after seeing his performance in Drohi, which had come after several box-office failures for him. Sharman Joshi's role was originally offered to Silambarasan, but after discussions, it was revealed that Silambarasan could not do as he felt he didn't suit the character. Subsequently, the role was offered to Siddharth, a protege of Shankar, who also went on to refuse the project. Despite further reports that Arya and Jiiva were being considered, the latter signed on and agreed with Shankar that he would play Joshi's role instead of Madhavan's. The role played by Kareena Kapoor in the original was offered to Asin Thottumkal. However Ileana D'Cruz was signed on for the film after attempts to cast Katrina Kaif in the film had failed. The college professor's role was given to Sathyaraj, despite early indications that Prakash Raj would be approached. Omi Vaidya was unable to reprise his role from the original and comedian Sathyan Sivakumar was signed on to essay his role after attempts to sign Sricharan of Payanam fame has failed, while S. J. Surya signed on to appear in a guest role, portraying the role enacted by Javed Jaffrey. Anuya Bhagvath was signed up for a supporting role. Stage artist Sreedevi Gengiah was selected to play Jiiva's sister. Raju Jeyamohan was initially chosen to play the older version of Rinson Simon's character Millimeter, but was later removed as his eyes did not match Rinson Simon's; the role went to Vikas. Filming The first schedule of filming was held in Ooty, where scenes involving Ileana, Srikanth and Jiiva were shot. During the second schedule scenes involving the lead cast were canned at Forest Research Institute, Dehradun and Pondicherry Engineering College, Pondicherry and a car chase at various places in Chennai, while two songs were filmed in London and Buckingham during the third schedule. Some significant parts of the film were shot in Chennai at Sun Studios, Kothandapani Studios and the Ampa Skywalk Mall, as well