A cop, who sets out to solve the mysterious death of infants in Kumbakonam, realises that a few bigwigs are behind the crime.

A man who wants to leave his shady life behind gets embroiled in a web of conspiracy where the perpetrators are sinister politicians, corrupt police officers and seedy gangsters.

Vishal (Riaz) and Dr.Vasudevan (Yog Japee) wake up one day to find out that they both are stuck inside a square room devoid of any furniture. The only other element in the room apart from the two of them is the dead body of a man lying in the middle of the room, blood soaked. Vishal and Dr.Vasudevan do not know each other. Soon, Vishal realises that there is a tape recorder near him, he finds a cassette in his pocket, which he plays. The cassette welcomes him to the SQUARE and tells him that his only way of escaping is by finding a clue that only the guy opposite him can see. Soon, Dr.Vasudevan plays the cassette from his pocket and the recording again welcomes him to the SQUARE and tells him that he has been doing a lot of good by saving lives as a Doctor and yet he has committed a grave mistake which he is now getting punished for. He is told that there is only 8 hours remaining for him to escape and his escape would only be by killing the one opposite him.

Nandha (Nandha Durairaj) is an upright sub-inspector of police who has been transferred 15 times in three years. He is then transferred in a police station based in Pollachi. There, Police Inspector Pandian (Natarajan Subramaniam) is in the pay of Minister Periyannan (Rajagopalan), who runs in own government in the place. Nandha is shocked to note that Pandian and the entire police department are corrupt. Thereafter, Nandha tries hard to enforce the order. Soon, both policemen clash. Pandian becomes an honest policeman after Periyannan’s men attempt to kill him, and he is revived with blood transfusions from the public. However, Nandha does not believe that he has truly changed. After a fellow honest sub-inspector gets killed by Periyannan’s men, Nandha blames Pandian, and through short routes, becomes inspector himself. He arranges for Periyannan and his men to clash with Pandian, but in the ensuing fight, Pandian kills them all, while Nandha walks away.