A group of peoples are shown falling dead due to the addiction on drugs in Bhavani, one of the place in Erode District. One of the child named Pragalya's death impacts the public very badly.
The police department is pressurized by the government to form an undercover investigation to find about the person who had been involved in the business of drugs in the Erode district. The police department appoints John William David, a police officer from Chennai to investigate the case. David recalls his life before 2 years when he was posted as ACP of Chennai. He was a honest police officer who was in-charge to eliminate an important criminal named Rajiv Reddy who was escaping the law in all ways.

His mentor and godfather JCP Rathinavel gives him an unofficial charge to encounter Reddy. John manages to kill him but in the process loses his wife Dhivya and child Esther. But, still continued his duty despite the loss of his family. John forms a secret team to investigate about the drugs that the childrens had consumed.

Co-incidentally, John's close friend and Rathinavel's son Harsha Vardhan has come to Erode for joining as an NCC master in SVN school. After meeting John, they both stays in the same house.

In a parallel incidents, One day, Harsha...