Pandiarajan wanted to act in films. But due to his height and appearance he decided to join as an assistant director. He joined Thamizisai College where he had learnt violin and got his diploma as “Isai Selvam” in 1977. After that he had joined writer Thooyavan as an office assistant. Here he met director K. Bhagyaraj and later joined him as an assistant director. He had become his associate director in Darling Darling Darling and worked till the discussion of Munthanai Mudichu. Pandiarajan told the story of the film kanniraasi to Sivaji ganesan’s brother shanmugam, he listened to the story and accepted it, though financiers refused to buy, the film was successful at the box-office.
His first directorial venture was Kanni Rasi in 1985 starring Prabhu and Revathi. He directed and made his debut as a hero in Aan Paavam. Till now, he had directed nine films, including Kaivantha Kalai, Doubles where he directed prabhudeva in the lead role and acted in some 90 Tamil films and one Malayalam hit Kathavasheshan, where he acted with Dilip. Recently, he is acting in a TV serial called Mama Maaple in Sun TV. His English short film called Help has been nominated at the ArtDeco Film Festival 2011, at São Paulo, in Brazil. ‘Help’ is Pandiarajan’s first short film in English.
He ran away from his village at the age 13 due to his father’s scoldings. He first worked in an oil mart, then in a private wine shop as a waiter and then landed up in drama where he started developing his skills. His first film was Ithikkara Pakki (1980). He slowly entered the Tamil film industry in small characters and finally landed in a good role in the film Malayoor Mambattiyan. He has acted in many popular films with several of the leading actors and comedians in the south Indian cine industry. He usually appears in films with Goundamani in a slapstick double act. Together they have formed a comic pair in many Tamil films and was known as the Laurel and hardy of Tamil Cinema. Recently, Senthil has started acting in Tamil tele-serials.