Malathi is a new teacher in a small town and stays in the house owned by Raja, another teacher at the school. Raja's older brother is an Army officer that everyone calls Pattalathan. He's well-respected in the town and is strict with anyone that attempts anything illegal or immoral. Vasu is a moonshiner that has had multiple run-ins with Pattalathan and nurses a grudge. His younger sister Ranjitham was in college with Raja. The two were in love but separate due to misunderstandings caused by their older brothers' clashes. Raja arranges for Malathi and Pattalathan to marry and the two are very happy together. Ranjitham's other brother Arunachalam, who ran away as a child, returns to town just as Pattalathan is deployed again. Malathi knew Arunachalam before she came to town and that prior relationship causes problems for the family. Things are exacerbated when Malathi learns that she is pregnant. The family tensions reach a critical juncture when Pattalathan returns to town.