Purushottam aka Porus is an aspiring police trainee, whose aim is to become a IPS officer. He hails from a middle-class family consisting of his father, sister Dwaraka and her mother. However, their happiness is short lived when Dwaraka is kidnapped by influential industrialist Nedunchezhiyan's brother Elanchezhiyan aka Ela, but manages to escape where she is killed by Nedunchezhiyan and Ela, as she witnessed the murder of a social activist named Parishuddam, when he started a protest against his factory, which destroyed a prosperous village. Dwaraka's murder is placed on her eve-teaser Guna, the brother of a local don named Selvam.

However, Porus learns that Guna has been murdered in prison and decides to investigate in his own way where he uncovers some brutal murders, which is orchestrated by Nedunchezhiyan and his gang. Porus finds out that a girl named Divya was to be abducted by Ela, but Dwaraka was accidentally kidnapped by him. Nedunchezhiyan's men learn about this and attack Divya, but Porus arrives in time and thrashes the goons, but can't save Divya. However, Porus' friend Faizal, who was killed by Nedunchezhiyan's gang, had received a recording of Dwaraka's confession about the murder and stores it in his phone. Porus tells a hacker to check Faizal's phone and the hacker gives the recording to Porus and learns about Parishuddam's murder.

After learning from his henchman, Nedunchezhiyan kidnaps Porus' father and tells Porus to hand over the recording or else he would see his father die. Porus brings the recording where he is thrashed by the gang, but Porus retaliates by thrashing the gang and also kills Ela. Porus brings Selvam where he tells him to avenge Guna's death. Selvam kills Nedunchezhiyan with a Chainsaw, while Porus leaves the factory with his father. With Divya's father's help, Porus stuffs a dead Nedunchezhiyan and Ela into a meat grinder and feeds their flesh to a crocodiles in a zoo (where Divya's father works) as there would be no evidence about their deaths. After this, Porus is finally appointed as an IPS officer.