Karthik (Naga Chaitanya) is a mechanical engineering graduate who wants to be a filmmaker. Karthik’s family rents the ground floor of a two-story Alappuzha house that belongs to a conservative Syrian Catholic that lives upstairs. Jessie (Samantha Ruth Prabhu), their daughter, is two years older than Karthik. She has a brother, Jerry (Sudheer Babu). When Karthik meets Jessie for the first time, he falls in love with her. Karthik expresses his love to Jessie, who is afraid of speaking to men around her strict father, and ends up angering Jessie. Later Jessie goes to Alappuzha, her grandparents’ place. Karthik gets to know this from his sister and goes to Alappuzha, along with his friend Krishna, where he gets introduces to her family as his classmate. Then Karthik tells her that they can be good friends. After coming to know from her that she is going back to Hyderabad alone, he decides to turn the friendship in to love in the train journey. In the train, he kisses her for which she slaps him and later the two meet several times afterwards and Jessie begins to admit that she likes Karthik but wants to refrain from any problems because she knows her father won’t accept a Hindu marrying their daughter. Now, Jerry finds that they like each other and in the fight that follows we come to know that Karthik is a part-time boxer where he beats up Jerry and his friends. Her parents learn about their affair with this fight and arrange a marriage for her. But at the wedding, she refuses to marry the groom, Roy Thomas (Surya), displeasing everyone in her family. Karthik and Jessie continue to love each other without the knowledge of their parents. Suddenly, Jessie is forced by her father to marry and seeks Karthik’s help, who was in Goa for a film shooting. Busy Karthik is unable to attend to her calls and messages; Jessie is unable to reach him. After a tense phone call from Jessie, Karthik goes back one night to check on her. An angry and hurt Jessie makes a final decision to break up with Karthik because of her father’s strong disapproval of their love.

Later on, Karthik learns that Jessie got married and is settled abroad. Two years later, Karthik meets Nandini, who falls in love with him. She is rejected by Karthik who cites his previous affair with Jessie whom he can not get over. He then comes up with a script for his first film, which happens to be his own love story. He calls upon Silambarasan as the film’s protagonist and Trisha as the female lead. The film is eventually titled Jessie.

He sees Jessie three years later in the U.S. and thinks she is married. She reveals that she is not. She refused to marry anyone her parents set up because they rejected Karthik. Out of anger, her parents leave. They then get married at a Hindu temple and a church. The film ends at a theater where they watch Jessie.