Karthik (Silambarasan) is a graduate Mechanical Engineering in Chennai who aspires to become a filmmaker. His friend introduces him to cinematographer Ganesh (Ganesh Janardhanan). With Ganesh's help Karthik becomes an assistant to director K. S. Ravikumar. Karthik's family, who are Tamil people Hindu's, rent Jessie's (Trisha Krishnan) house. Jessie is from a conservative Malayali people Saint Thomas Christians/Syrian Catholic family from Alappuzha, Kerala, that lives upstairs.<ref name="manorama"></ref> Karthik falls in love with Jessie the moment he meets her. Karthik tries to interact with Jessie, who is afraid of speaking to men around her strict father, and ends up angering her. Unable to hide his feelings any longer, Karthik confesses his love for her; she does not respond. A few days later, Karthik learns from his sister that Jessie has gone to Kerala to visit her grandmother. He and Ganesh end up in Kerala to look for her. After several days, he finds her and apologises. She introduces him to her family in Kerala as her "classmate". Jessie denies she has any feelings for him but agrees to be his friend. On the train journey back home, however, the two get close and share a kiss. Karthik is convinced Jessie loves him; the two meet several times and Jessie begins to admit that she also likes Karthik, but wants to refrain from any problems because she knows her father wouldn't give her hand in marriage to a Hindu. Consequently, due to various misunderstandings between Jessie's brother and Karthik, her parents learn of their supposed affair. They fix a match and schedule her wedding. The day arrives and midway through the ceremony, Jessie refuses to marry the groom, displeasing everyone in her family. Karthik, who had, without anyone's knowledge, come to Kerala to witness the wedding is ecstatic and secretly visits Jessie at her home. It is then that Jessie admits she has indeed fallen in love with him. Karthik and Jessie continue to love each other without the k