Vairavan and Mathangi are loving brother and sister in the village Vengaivasal.

The opening scene starts with two kids jumping into a well. One of the villagers come to Vairavan’s house and seeks help as his tractor and says police were disrespectful to him. Vairavan's wife assures him that Vairavan will help. Then we can see hitmen were hired to kill Vairavan. He beats them up for killing a dog without knowing they came to kill him. It is established that Vairavan is a village don and respected wealthy man who does good for everyone in the village. Mathangi and her husband Sargunam, who is a school teacher, are introduced as a loving couple. Sargunam does not speak to Vairavan due to differences in their philosophies. Sargunam believes that everyone must go to court and not practice violence like Vairavan.

Vairavan’s son Vivek is studying in the US, and when he comes back to visit the village, he meets Sargunam and reprimands him, saying that he does not need his family. In the flashback it is revealed that the two kids which earlier fell in the well were Sargunam’s son and Vivek. Mathangi sees them and jumps to save them. She is not able to save both, and hence, she leaves her own son to save Vivek. Sargunam blames Vairavan for his son’s death as he believes it is his influence that made him fall into the well. Mathangi loves Vairavan and hence vows to make them together and not speak to Vairavan until her husband speaks to him.

Meanwhile, they propose to surge an alliance between the two families through marriage of Vivek to Sargunam’s daughter Keerthana. When the marriage was about to take place, Keerthana is stabbed, and Sargunam blames Vairavan’s violence for it again as neither he or Keerthana has enemies.

Vairavan deduces that the person who stabbed his niece is Adhiban, who acts like a good man to the villagers but in reality has bad intentions and is a serial sexual assaulter. Vairavan is being searched by police for beating up people. Sargunam provides information to the police on Vairavan’s whereabouts near to Adhiban’s house. Mathangi visits Adhiban’s house and kills him as he tries to molest her. She learns that he also sexually assaulted Keerthana before stabbing her. The reason for stabbing her was Sargunam’s case on his borewell. Vairavan disposes his body off.

Sargunam learns of all this and understands his brother-in-law and the families unite.