Aayirathil Oruvan (transl. One in a Thousand) is a 2010 Indian Tamil-language action-adventure film written and directed by Selvaraghavan and produced by R. Ravindran. The film stars Karthi, Reemma Sen and Andrea Jeremiah with Parthiban playing a pivotal role. It revolves around three characters, Muthu (Karthi), Lavanya (Andrea Jeremiah), and Anitha (Reemma Sen) who embark on an adventure to search for a missing archaeologist. It is inspired loosely by the historical decline of the Chola dynasty and the rise of the Pandya dynasty.

The film's principal photography commenced in July 2007, and continued till 2008; the shooting of the film took place in various locations with 2,000 extras in areas including Chalakudy, Kerala and Jaisalmer, Rajasthan, and also filmed in Ramoji Film City in Hyderabad. The title Aayirathil Oruvan is taken from the 1965 film of the same name. The cinematography was handled by Ramji and editing work is done by Kola Bhaskar. The film's background score and soundtrack album is composed by G. V. Prakash Kumar, replacing Selvaraghavan's usual collaborator Yuvan Shankar Raja, whom he composed for his earlier films. The soundtrack received rave critical acclaim and emerged as one of the composer's best works till date.

The film languished in development hell due to slow progress of the shoot and the extensive pre-and post-production works, evading release dates ranging one year, Aayirathil Oruvan was released during the Thai Pongal festival, on 14 January 2010. The distribution rights were bought by Ayngaran International. Though the original film length was 181 minutes, it was then trimmed to 154 minutes for the theatrical release.

Upon release, the film garnered critical acclaim from both the critics and audience, alike. The film developed a cult status over the following years. At the 58th Filmfare Awards South, the film won Best Supporting Actor award for R. Parthiepan.