Nathan,a police officer gives shelter to Kamala, poor disowned daughter in law of Dharmalingam and helps her to fight a case against Dharmalingam,a rich man. But Kamala is murdered on the way to the court hearing. Fingers point at Dharmalingam and his son Shankar . Shankar and Nathan's sister Uma are in love. Nathan comes to investigate the case and falls in love with Dharmalingam's daughter Sarasu . Now, Nathan is in a dilemma. Should he protect Shankar as he is his sister's sweetheart, or should he drop the case because he loves Dharmalingam's daughter? Or is the real murderer someone else?