Police war : The beginning

A group of people have been shown dying due to drugs in Bhavani, a place in Erode district.  One of the children, Prakalya's death, affects the public very badly.

 The police department is pressuring the government to set up a secret investigation into a person involved in the drug trade in the Erode district.  The police are appointing John William David, a Chennai police officer, to investigate the case.  Chennai's ACP  David recalled his life 2 years before he was appointed.  He was an honest police officer who was in charge of getting rid of the main culprit Rajiv Reddy who was escaping from the law by all means.

 His mentor and foreman, J.C.P.  Rathinavelle makes an unofficial accusation to confront Reddy.  John manages to kill him, but in the process loses his wife Divya and baby Esther.  But he continued his duty despite the loss of his family.  John forms a secret team to investigate the drugs the children have taken.

 Coincidentally, Harsha Vardhan, John's close friend and son of Rathinaveli, has come to Erode to join SVN School as NCC Master.  After meeting John, they both stay in the same house.

 In a parallel incident, one day, Harsha sees a school girl trying to take a drug and catches her to confront her about drugs.  At the bus stop, a vendor charges him Rs.  After throwing the drugs, he informs the SP and tells him to send a special force to a secret hideout.  This was witnessed by a school teacher who was a class teacher when Harsha was a student.

 But, Harsha explains to her the reason why he is a secret officer.  His father Raghavan, who was a wealthy businessman, was a respected man in Pollachi's Veeralpatti.  But some jealous people and his father's aides killed him for his position.  However, he escaped and was adopted by his father's brother Rathinavel, who was a police officer like Harsha.

 He trained him hard, and posed many challenges in his life to test his performance.  After overcoming all these obstacles he joins the IPS training and again Harsha is given a test to test his performance.  But, now it is a tough match for him.  He will have to face challenges as an undercover officer.  His teacher inspires him to fight against injustice.

 David learns that Harsha is a police officer and that his girlfriend Swetha supports him in his secret mission.  When David, Harsha and his group go to the bus stop, they find a piece of paper.  They feel that the culprit has escaped from that place.

 Later, John and Harsha collect the forensic reports of the dead children and are shocked to see it.  Children will be infected with an unknown virus after taking the medication, and they will die when they take too much of it.

 Harsha recalled her favorite drug from a little girl at school, realizing that it had been sold by a much-loved criminal.  They fortunately arrest one of the drug dealers in Erode, and realize that Anthiyur is a mastermind behind this scheme, a much-wanted criminal.  Vetrimaran is behind this plan to destroy India through a war of survival after being bribed by some Chinese people.

 Harsha and William kill the salesman when they learn that Vetrimaran is looking for a hideout on Lakshadweep Island.  With the Kerala and Tamil Nadu police teams, Harsha travels to Lakshadweep for a 12-day journey, which revolves around Vetri's hideout.  However, Vetri escapes on a ship, while Harsha and William destroy the entire island and the drug-carrying virus with their teams.

 Vetrimaran lands in Erode and abducts Swetha.  If Swetha wants to be alive, Harsha Anthiyur threatens to come to the reserved forests.  After a long battle, Harsha brutally attacks Vetri and explains the maintenance of the nation and the impact of the betrayal.  Vetrimaran realizes his mistakes and mistakes due to injuries and dies.

 Later, Harsha and John attend a press conference and send a message that it is their responsibility to prevent these dangerous crimes that are ruining the lives of children, the need of future generations.  Harsha's foster father gives him another trial, but now it's an official investigation, indicating that Harsha is ready to wage another war with the criminals.  He goes to Tirunelveli with John David and his wife Swetha, where he is scheduled to handle the case.

 On his way to Tirunelveli, David asks Harsha to tell him more about his father Raghavan, to which he replies that he is not his father, but actually his father-in-law who was killed in a riot 5 years ago when he was a police officer to control the riots.  .  He designed the story for the author in order to gain their support to destroy this dangerous business.  John David praises him for being a brilliant watchdog in crafting stories to stop these dangerous criminals in society, and urges them to continue this tactic in order to gain support from the general public.