Dr. Selvam (Kamal Haasan) is the new Vice-principal History professor in a college ruled by the Donor's son Ramesh (Karan) who is essentially a spoiled brat, who owing to the lack of parental guidance turns into a cruel and callous bully. He also negatively influences the other students in the college by his tyrannical use of money and power. However, under the transformational leadership of Dr Selvam, he is inspired to change his ways, and under their influence the milieu of the entire college is radically changed for the better.
Vasanthi (Gouthami) is also a Professor in the same college who initially disapproves of Selvam's methods, but later falls for him. Selvam is revealed a cancer patient, who is seeking answers to fight his inner demons by doing good to the college. When all his methods to insult Selvam fail, and when one of his gang turns against him, Ramesh retaliates by implicating his ex-friend's lover, who is also the Principal's (Nagesh) daughter in a brothel raid, which leads to her suicide.The inevitable final clash ensues, where Selvam still does not want to harm Ramesh and is still willing to offer him a second chance. In the end, Selvam and Vasanthi leave for the US seeking a cure for his Cancer and hoping that the college will be truly reformed when they return.