The film stars Karthi Sivakumar, Reema Sen and Andrea Jeremiah in lead roles. Parthiban also plays a pivotal role in the film. Aayirathil Oruvan tells a fantasy story that travels back and forth in time and is centered around four key characters. Reema Sen plays the role of a bio-scientist who invents a medicine with a potential to change the lives of people. Karthi plays a man who got transformed by the medicine. Shooting of the film began in July in 2007, but due to the extensive pre-production and post-production works the release of the film got delayed. The project started with an estimated Rs.15 crore budget but ended up with Rs.32 crores. Aayirathil Oruvan is produced by R. Ravindran. G V Prakash Kumar has scored the music for the film while lyrics are by Vairamuthu. Ramji has cranked the camera for the film while editing is by Kola Bhaskar. Aayirathil Oruvan is scheduled for release on January 14, 2010 coinciding with the festival of Pongal.