Saravana Silambarasan is a college student who returns home for his sister Divya's wedding with a distraught and frightened girl named Sadhana, whom Saravana introduces as his friend to his family. While the marriage preparations proceed, everyone starts to wonder what Sadhana's relationship to Saravana really is. Saravana's uncle Purushothaman begins to lose his temper as he wants Saravana to marry his daughter. Purushothaman confronts Sadhana, triggering an emotional confrontation. While at a restaurant, Saravana and Sadhana are confronted by a gang. Saravana chases the gang and thrashes them. Realizing that he has left Sadhana behind, Saravana returns to the restaurant, but finds that Sadhana is not there. Saravana's father Bhoopathi confronts Saravana and forces him to reveal about Sadhana's identity, where Saravana reveals his past.
Past: In the past, Saravana and Krishna Krishnakumar Ramakumar are best friends who visit Krishna's home village. Sadhana Jyothika returns from London and is impressed by Saravana, who continues to win her over with shared tastes. He gets along well with Krishna's and Sadhana's family. Saravana convinces them that he would be a suitable groom for Sadhana. Sadhana's family, mainly her brother Soundarapandiyan Prakash Raj and his sidekick Velu, are involved in the village's rival gang world. When Sadhana takes Saravana to the temple for a visit without Soundarapandiyan's knowledge, a rival gang headed by Duraisingam attacks Velu's group members, and Duraisingam's brother Vanjaravelu grabs Sadhana and threatens to kill her. In a swift act of bravery, Saravana defeats Vanjaravelu. After this incident, Soundarapandiyan explains the violence plaguing the village to Saravana.
Soundarapandiyan explains how he and his wife are master's degree holders from BITS Pilani. He also says that despite the violence, he aims to stay noble and uphold high ideals. A few days later, Duraisingam's gang intensifies their attacks and destroys Krishna's extended family, sparing only Sadhana. Saravana pledges to protect Sadhana and take responsibility for her future. He also becomes Duraisingam's rival after killing Vanjaravelu to safeguard Sadhana. When Duraisingam learns of Vanjaravelu's death at Saravana's hands, his focus shifts to killing Saravana rather than Sadhana.
Present: Velu tracks Sadhana and brings her back to Saravana's home. Fearing for her safety, Saravana plans to send her to London, but Sadhana resists, declaring her love for him. On the day of the planned flight, Sadhana meets a friend of Krishna at the airport and learns more about Saravana's devotion. She also knows that her family had chosen Saravana as her groom before the tragedy. Realizing she cannot leave him, Sadhana decides to stay. She eventually locates Saravana, who is in a confrontation with Duraisingam and his men. After a fierce fight, Saravana defeats Duraisingam, and the lovers reunite, while Duraisingam is killed by Velu.
