1996: In Ooty, Chozhan Ramalingam and Rajiv Paarirajan are two friends who are trained by Paarirajan, Rajiv's father who is an ex-CBI officer. He enables them to join the police force. Although given equal training, Chozhan appears to best out Rajiv, causing the latter to turn jealous of the former. One day, Chozhan and Rajiv are playing chess in which Rajiv wins. While Rajiv leaves Chozhan pondering over the outcome, he sees Paarirajan dead on the floor. The boys are escorted to the police station and although Chozhan tells the inspector and Ramalingam, Chozhan's risk-averse father, that he can bust the killer using his skills, Ramalingam takes Chozhan away, leaving Rajiv alone.

2021: Chozhan becomes a departmental store owner, run by Ramalingam in Singapore. However, he has now evolved into a part-time vigilante and secretly thwarts minor crimes and corruption to help the Tamil community, One day, a gas company near his store suddenly bursts, which kills 11 Tamil people and severely injures five more. Chozhan nabs Joseph, the painter, who is behind the mess and hand him over to the police. The next day, the Indian External Affairs minister, who comes to Singapore to address the Tamil people struggles to speak at the gathering and Chozhan immediately senses that her artificial cardiac pacemaker had been tampered with, and shoots to save her.

Chozhan is caught by the police but is later released after they realized that he saved her. As soon as Chozhan tips off the police, they capture the culprit at a hotel revealed to be Rajiv, who is now a hardened assassin, who was hired by the Beijing corporate businessman to kill the External affairs minister. However, Rajiv escapes by threatening the policemen by killing their families. Chozhan meets up with Rajiv, who reveals the incident that happened on the day they separated: Rajiv was confronted by Paarirajan who berated him for misusing his skills to loot some money, which made Rajiv kill his father. He also overheard him saying that Chozhan would eventually overshadow Rajiv in anything, thus inciting him to develop a permanent deep hatred for Chozhan.

Upon hearing this, Chozhan warns that he would pay for his mistakes. Instead, Rajiv argues that he has evolved and grown in multiple ways and is way too advanced for Chozhan to intercept, while challenging him to rescue one of his close ones that he would soon kidnap. Chozhan calls everyone for a surprise engagement with Ashvitha. He did this to make sure his loved ones are always with him so none of them get kidnapped by Rajiv. At his engagement with Ashvitha, Chozhan realizes that his cousin's daughter, Pinky has gone missing from her school excursion. Soon, Rajiv contacts him and informs him that he kidnapped Pinky from her school to kill her, but Chozhan responds by abducting Rajiv's pregnant wife Anisha. Chozhan threatens to kill Anisha if anything happens to Pinky.

Chozhan and Rajiv meet in order to exchange their kins. As Rajiv releases Pinky over to Chozhan, Chozhan says that he would not let go of this issue easily. He makes a deal with Rajiv: he will safely transport Anisha back to India if Rajiv surrenders to the police for the deaths of the 11 people. Rajiv agrees reluctantly and surrenders himself. As Chozhan transports Anisha to the airport, The hitman, who was sent by Beijing businessman to kill Rajiv learns about Anisha's connection to Rajiv, where he follows and slits her throat in the washroom. In prison, Rajiv finds out about Anisha's death on TV and is anguished. He thinks Chozhan had broken his deal and escapes the prison, by swallowing prawns making him choke and allergies. He plots against Chozhan by kidnapping the children of his area and addresses the community that in order to save their children, Ramalingam must die.

Rajiv attempts to brainwash someone into shooting Ramalingam to ensure the safety of their children. No one does so, so Rajiv extorts Ramalingam alone to commit suicide by drinking rat poison. In the meantime, Chozhan saves the children. When Chozhan returns to his community with the children, Ramalingam dies, not before telling Chozhan to finish Rajiv. Chozhan confronts Rajiv inside a skyscraper and after an intense combat, Chozhan kicks Rajiv off the building and grabs him by his leg. In the end, he divulges that he wasn't Anisha's murderer and the Beijing corporates were behind it. Rajiv gets shocked after knowing the truth and tries to convince Chozhan to pull him up, but Chozhan drops him off the building leading to his death. Several years later, Chozhan takes his son and lays flowers on his father's grave, and also on Rajiv's grave.