Sri, an engineering graduate from small-town Trichy, arrives in Chennai to interview for an IT job in Business Process Outsourcing.[6] Sri passes his interview with HR officer Regina Cassandra and celebrates at a bar with his friends.

Another man at the bar, Sundeep Kishan, has had an unrequited love for Regina since they were in college. In a flashback, goons threaten to throw acid in Regina's face if she falls in love with Sundeep. Enraged, Sundeep punched one of the goons. In the present, the goons recognize Sundeep in the bar and hire some gang members to beat him. However, the gang members mistake Sri for their target and beat him when he leaves the bar, knocking him unconscious and stealing his phone and bag, throwing the latter into a taxi cab.

Charle came to the city to seek medical treatment for his son while driving a taxi rented from gangster PKP. He finds Sri's bag in his taxi with his academic certificates, which he takes to the police station. In the morning, Sri awakens in the street and calls a friend to take him home. He boards a bus to his new job, to explain about his missing academic certificates.

Sundeep boards the same bus to attend a job interview at Regina's company. He recognizes the goon who threatened Regina and attacks him with acid then escapes with his friends. Sri is detained by the police, having unwittingly passed the bottle of acid to Sundeep. Fatigued by the hostility of the city, Sri argues with the police inspector who beats him until a constable intervenes. The constable talks with Sri at a tea stall, where Sri recognizes the man who told him to pass the acid bottle, and the constable arrests him.

The gang members plot to kidnap schoolboy Karthi for ransom, sending a man named Winnings to trick his teachers. Winnings is unprepared when there are five boys named Karthi, one of whom volunteers to go with Winnings in order to avoid a mathematics test. They take the boy but later realize he is the son of gangster PKP.

Sri tells Regina that he no longer wants the job. She asks him to take the company's training so that she won't be held responsible for his quitting. They begin to argue about it and Sundeep, who is waiting for his interview, intervenes. The police arrive and take Sundeep away, saddening Regina who loves Sundeep but cannot accept his carefree nature. Sri tells Regina that he lost his academic certificates, and she agrees to cover for him for a day.

PKP orders his henchmen to hunt down his enemies in a search for Karthi. The gang demand a ₹1 crore (10 million rupees) ransom and PKP agrees to follow their instructions. Meanwhile, Sundeep is released by the police inspector, who is his uncle. Sundeep waits for Regina at a bus stop outside her hostel. Regina sees Karthi, who had escaped the kidnappers, hiding in a truck and instructs Sundeep to take Karthi home. Sundeep tries to call PKP but his phone is off. He then meets his uncle and leaves Karthi in the police inspector's custody. Winnings, who is terrified of PKP, confesses the kidnapping to the inspector, who commands Winnings to go through with the ransom exchange. Sundeep arrives and realizes the situation. The inspector shoots PKP and tries to shoot Winnings but Sundeep shoots the inspector in the leg and instructs Winnings to take PKP and Karthi to the hospital.

Meanwhile, Sri is riding in Charle's taxi when they are stopped and attacked by the gang who believe they are spying for PKP. They threaten to kill Charle if Sri does not bring PKP. To allow Charle to escape and take care of his sick son, Sri fights back against the gang who he recognizes as his attackers from the bar.

Sri's lost academic certificates are returned to his home address. Outside the hospital, Sri and Sundeep each talk to their girlfriends. They are about to introduce themselves to each other when they are challenged by another gang hired by the goon Sundeep punched. Sundeep and Sri charge toward the gang to defend themselves.