Siruthai is a 2011 Indian Tamil-language action comedy film directed by Siva and starring Karthi in dual roles alongside Tamannaah Bhatia and Santhanam.
The story revolves around Rocket Raja, a petty thief who comes across a little girl claiming he's her father. When he learns the truth about his lookalike Rathnavel Pandian, an honest cop, he decides to turn a new leaf and help get rid of a crime gang.
Produced by K. E. Gnanavelraja and featuring music by Vidyasagar, Siruthai was released during Pongal on 14 January 2011. The film received positive responses and was successful at the box office, leading to Siva being known as "Siruthai Siva" from then on.