Siruthai (English: Leopard) is a 2011 Indian Tamil action comedy film directed by Siva.It is a remake of the 2006 Telugu film Vikramarkudu, directed by S. S. Rajamouli. It stars Karthi, performing dual roles, and Tamannaah alongside comedian Santhanam. The film was produced by K. E. Gnanavelraja and features music by Vidyasagar. It was released during Pongal on 14 January 2011. Despite gaining mixed critical response, the film was a success at the box office.
Rocket Raja (Karthi) is a small-time thief who steals anything he comes across. With his partner Kaatu Poochi (Santhanam), he enjoys life to its fullest and even falls for the beautiful Swetha (Tamannaah). However, his life changes when a small girl Divya Rathinavel (Baby Rakshana) ends up in his care; he looks exactly like her father Rathnavel Pandian IPS (Karthi).
As Raja discovers the girl's past, it is revealed that Pandian is an honest policeman who is a nightmare to criminals, but that one gang of criminals in the village of Devi Pattnam are intent on killing him and his daughter because he killed the son of a prominent criminal Bavuji (Avinash), who also sexually abused women. Pandian's colleagues put Divya in Rocket Raja's care so that the criminals cannot track her. Pandian is on the verge of death following a gunshot to his head. At first, Raja is angry with the little girl and breaks her tape recorder. Divya is happy and hugs him, after he repairs it. Pandian is intent on fighting back.
Unfortunately, he dies following a battle with several criminals who had been chasing Raja and Divya. From police officers, he realizes that Pandian was an honest and courageous police officer who stood against Bavuji and his family, who had cruelly ruled a village. Pandian even manages to kill his son and stops their criminal acts. He also manages to fail his brother but he gets shot when he tried to save a child.
Upon seeing his courage, Rocket Raja (with the help of Pandian’s colleagues) steps into Pandian's shoes and finishes his unfinished work as he himself is a thug and destroys all their properties with the help of Kaatu Poochi in a hilarious way. He also kills his brother and also takes on the responsibility of taking care of Divya, with the help of Swetha.