Ponnar Shankar is a 2011 Indian epic historical drama film produced and directed by Thiagarajan. It is a fictionalised account of the Ponnar Shankar epic, adapted from M. Karunanidhi's novel of the same name. It features Thiagarajan's son Prashanth in lead dual roles as warrior princes, portraying the title characters, with actresses Pooja Chopra and Divya Parameshwaran making their film debut as princesses. The film also features an extensive cast of supporting actors with Prabhu, Napoleon, Prakash Raj, Jayaram, Sneha and Kushboo amongst others. The background score and soundtrack of the film, composed by Ilaiyaraaja, was released on 27 March 2011.
Filming, although significantly delayed, began in August 2009 at Valluvar Kottam in Chennai, where an ancient township film set with temples, forts, a lake and palaces had been built. The film's producers encountered difficulties in making prompt payments to its crew that consisted of more than 1000 members during the filming in the forests of Pollachi. The filming then shifted to Guindy National Park in Chennai, with the battle sequences shot in Kerala and Karnataka.
Prior to its release, the film drew criticism from the Kongu Nadu Munnetra Kazhagam (KMK) Party with an unsuccessful petition filed at Madras High Court seeking a ban on the film, claiming that it portrayed the traditional deities of the gounder community in a bad light. The film was released on 9 April 2011 to a mixed response from critics. Although praised for its cinematography and art direction, it was criticised for having a weak plot and character deficiencies. The film was later dubbed and released as Prashanth Veer in Hindi and then as Rajakota Rahasyam in Telugu in 2012 and 2013 respectively.
A love affair between Thamarai (Kushboo) and her maternal uncle Nellaiyankondan (Jayaram) is badly received by their family, especially since he is not financially well off. Thamarai's father, King Periyamalaikozhundhu Gounder (Vijayakumar), arranges for her marriage to Mandhiyappan (Prakash Raj), ruler of a neighbouring country. Thamarai rejects the arranged marriage, angering Mandhiyappan. She later marries her lover, who had come to see her marry Mandhiyappan, and challenges her brother Chinna Malaikozhundhu (Ponvannan) to marry his daughters off to her sons (the marriage of cousins is a gounder custom). Periyamalaikozhundhu disowns his daughter for choosing Nellaiyankondan and banishes them from his kingdom.
Many years later, Mayavar (Nasser), a chieftain of a village in Periyamalaikozhundhu's kingdom, encounters twin brothers Ponnar and Shankar (both played by Prashanth), who are being tutored in martial arts by Rakki Annan (Rajkiran). Ponnar and Shankar are valorous and compassionate to the sufferings of the poor. One day, the twins save two sisters, Muthayi (Pooja Chopra) and Pavalayi (Dhivya Parameshwaran), from death. The girls are later revealed to be daughters of Chinna Malaikozhundhu. Impressed with Ponnar and Shankar's valour, Chinna Malaikozhundhu agrees to marry off his daughters to them.
A flashback reveals that Ponnar and Sankar are actually Thamarai's sons and that Rakki, who was then a servant of Nellaiyankondan, had saved the twins as small children from Mandhiyappan. Mandhiyappan had attempted to avenge himself on Thamarai for rejecting his hand in marriage. He learns that the twins are still alive and hatches a conspiracy to kill them. He tricks Kali Mannan (Napoleon) and Thamarai's father into helping him. This leads to an intense battle which ends with good prevailing over evil.