The task of collaborating with SP Loganathan is assigned to Prakash, a recently engaged DSP trainee, by ADGP Mahendran. With the new technical assistant, Veena, Loganathan grudgingly agrees to mentor him. The group left Chennai for Trichy to investigate the horrific killing of a young girl in the forest. The woman was strangled from the front with an iron wire while kneeling and having her hair pulled back, according to the doctor, who also believes that a big man's power must have been responsible for the wire's severe knife-like cut. According to a hematoma on her neck, the victim was knocked at certain pressure areas on a combination of muscles to knock her out before she was taken. Loganathan predicts that, given how peculiar the circumstances are, there will be other murders.
As predicted, a few more young women—including the daughter of the police constable—are killed comparably and then have their remains discarded in the woods. None of the victims had any connections or anything exactly typical, other than their ages (early to mid-20s) and the reality that they were all killed in the same way and deposited 4-5 kilometers from their homes. After initially being at odds, Prakash and Loganathan grow closer as they cooperate to solve the crimes and come to see how dedicated one another is to the cause. Prakash begins to like the way Loganathan approaches the case as well. Loganathan concludes later that the killer must be a psychopath with an inferiority complex who compensates for his low self-esteem by placing his victims in a submissive position with their eyes gazing directly into his eyes, then murders them to release his pent-up anger on someone else. The killer's mode of operation and the employment of arbitrary women both lend credence to this hypothesis.
Further investigation led them to the conclusion that the killings were a string of copycat homicides of women that occurred between 1973 and 1979. Loganathan, who poses as a friend of Inspector John Sebastian, visits his home, pretending to be the person who looked into the initial murders in the 1970s when Prakash visits the district library to find out the patrons who read books on pressure points. Books must have been the only source of information for pressure points back in the 1970s for a layman. Loganathan is instead greeted by Kennedy, John's son, who explains that his father went away many years ago. He also tells him that his wife recently died and that he has a son who studies in New Delhi. When tea is provided to Loganathan, he speculates that Kennedy may have OCD because he is so particular about order and perfection. Due to his physique and obsession with maintaining an orderly and immaculate home, Kennedy is believed to be a serial killer.
Kennedy is the name of the killer, according to Prakash, who finds Kennedy's name on the list of "Vital Points" book's readers. Kennedy is the name of the killer, he tells Loganathan. Prakash also rents a nearby property to spy on Kennedy in the area and gather solid evidence. However, they cannot uncover any substantial or damning evidence linking Kennedy to the most recent killings. Additionally, a different unidentified suspect is detained by a competing local police agency, and the local media reports that he has confessed to being the serial killer. To everyone's surprise, he committed suicide the following day. Prakash and Loganathan, however, refuse to accept that he is the real murderer and are entirely fixated on Kennedy. Kennedy surprises Prakash one evening while he is following him through a grocery store and says he wants to invite him over for dinner that night. Prakash enters a locked, dark room as Kennedy is cooking. This chamber caught his interest earlier when he broke into Kennedy's residence to gather evidence. Behind the frame of a picture that is hanging on a wall, he discovers a victim's picture.
Kennedy creeps up behind him and knocks him out by striking the pressure spot on his neck. Kennedy is held at gunpoint by Loganathan as the doorbell rings, and he also saves Prakash. Kennedy admits to the murder he committed as a youngster in the 1970s. He describes his past and the reason for his murders. John F. Kennedy's father was a pedant and a violent man who thrashed Kennedy to keep everything tidy, orderly, and clean. He also always demanded perfection from Kennedy in everything. When Kennedy's teacher discovers him smoking, the latter threatens to tell his father about the behavior. Kennedy attempts to stop her but accidentally kills her in a back attack. Kennedy, the perpetrator, meticulously removes all traces of his crime and disposes of his victim's body. Kennedy receives a little respite from his father for a few days as a result of his father's active and irate investigation of the murder case. He says the case is "cold," and his father starts beating him again.
Kennedy concluded that the only way he could protect himself from his abusive father was to continue killing random, innocent women. Kennedy assures the two that he has not committed any murders since that time and has kept everything a secret. Kennedy acknowledges that he had a strong aversion to seeing the faces of his victims. Kennedy does not fit the profile of the latest serial killer, Prakash realizes. After being questioned further, he admits that he was attacked a few days prior while blindfolded by an anonymous attacker who claimed to be familiar with him from the 1970s and forced him to reveal his pressure point attacks. All he could recall about the faceless attacker was that his automobile had an odd reverse gear alarm that sounded like a shooting toy weapon. Loganathan continues to demand that Kennedy be prosecuted for his prior crimes, but Kennedy maintains that his son shouldn't be aware of his former status as a psychotic serial killer. For his kid to obtain insurance money, he forces Prakash and Loganathan out of the room, locks himself in, switches on the gas, and instantly explodes, killing himself.
Prakash, who discovered the victim's scooter in an auto service shop, recalls hearing the same alarm tone at the time. He dashes to the mechanic, who offers to transport them to the NGO worker's home and claims that the car belongs to him. They force open the locked door and examine the rooms for pictures of the most recent victims. They learn that the suspect is a huge man who was subjected to abuse from his unfaithful wife, who would bring her partners to the house while he was there, and that it appeared at one time that he killed his wife and her boyfriend out of rage. He targets women with dimples because his wife has one on her cheek. Some banknotes from a neighboring coffee establishment are also discovered. The two go straight to the coffee shop, where they discover that the killer has been frequenting it for the past two to three days. Always sitting near a glass window, he would gaze at a singing poster that had been erected in front of the competing hotel.
Loganathan immediately goes to the lead singer's hotel room and finds that he is safe. In the meantime, Prakash notices that Veena's hotel is also visible and is surprised to see that she, too, has a dimple. They were conversing on the roof a few days prior, where it was easy to see the cafe. Veena encounters a huge man choking in the hotel hallway who begs her to get medicine from his car outside the hotel. Prakash calls Veena and informs her that the killer is going to target her next while she is close to the automobile. Suddenly, she turns around to see the big man standing next to her and grinning ominously. He knocks her out by pressing a pressure point on her neck, then takes off in the car with her.
After giving chase, Loganathan and Prakash discover that they are now stranded in a dark, dense forest. A flock of birds takes off unexpectedly, alerting them to the killer's position, and they fly to save Veena. The assailant stabs Loganathan from behind, rendering him helpless, as Prakash is freeing Veena from her tie. He then attempts to kill Prakash using Loganathan's gun but discovers that the stovepipe of the gun is broken. He then uses the pistol to assault Prakash, who catches it, pulls the trigger, and shoots the assailant in the eye. Prakash and Veena hurry Loganathan to the hospital after the murderer is killed. A few days later, Prakash gives his music player to a neighboring youngster whose parents are always bickering. After listening to music on it, the boy is comforted. Prakash has also spoken with the mother about how her son's mental disorder is a result of their frequent arguments. After giving her son a tender hug, the boy's mother is shown promising him that they will stop fighting. Loganathan and Prakash heads up to solve their next case.
