A soldier and a police officer join forces to bring down a cyber hacker.
50 robberies occurred on Independence Day, with two masked robbers looting houses. The entire police force is clueless without the slightest lead or evidence. ACP Gayathiri is assigned to the case investigation. Gayathri learns that the 50th house belongs to her ex-boyfriend Major Chandru. Chandru's grandmother gets injured in the theft in an attempt to safeguard the Ashoka Chakra medal, which was bestowed on Chandru's late father. Chandru joins Gayathri in the investigation to retrieve the medal and solve the case. Chandru checks the case details and information from the victims, only to realize that the robbers knew the exact location of the jewels in every house.
Chandru lists down the people who can get access to houses and realizes that a company known as Dial For Help may be involved in the case and all 50 houses had been serviced by the company under a common number belonging to a person named Marimuthu. The police rush to Marimuthu's house, only to find his wife there. Marimuthu's widow explains that her husband had died two years ago. Chandru, with no other clue returns. Meanwhile, a mysterious person calls the Commissioner and informs him that he was responsible for all the thefts thus far and challenges the entire force that no one would be able to track him down. Accepting this as a challenge, Chandru tries to provoke the unknown person, who gives a clue to his location. They realize that it refers to a place, and they rush to the place, only to find destroyed computers. Chandru heads back to share the clues, where he reveals that the clue refers to the queen in chess and that the hacker had left a partial thumbprint on the scanner used to destroy all data.
Chandru further reveals that thefts would occur in 58 more houses on August 23 due to the PM's arrival, where he tells that the hacker is actually a woman named Leela, a chess coach. A young Leela loved her mother tremendously and both of them had a bond with each other, but her alcoholic and abusive father tortured her mother. One day, Leela woke up to find her mother died in her sleep. Her father immediately married another woman and arrived home with her two young sons. Later Leela's father revealed that he and his new wife had suffocated and killed Leela's mother. An enraged Leela killed both her father and stepmother, and she uses her stepmother's two sons as baits for her thefts. A cat-and-mouse chase begins between Leela and Chandru where Leela makes several attempts to kill Chandru and his team. Chandru manages to capture Leela and hands her over to the police. Chandru gets a call from Leela, who escaped and challenges him for another game.
