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 (Prakashraj), 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 Sankar (both played by Prashanth), who are being tutored in martial arts by Rakki Annan (Raj Kiran). Ponnar and Sankar 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 Sankar's valour, Chinna Malaikozhundhu agrees to marry his daughters off 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.