Two Special Task Force teams, one led by Kathir and the other by Tamizh, captures a suspect related to an attack. The investigation reveals that an attack is planned in Chennai. However, even after a thorough investigation, the STF fails to obtain any concrete clue or information.
While Vishwanath, the Superintendent of Police, gets busy with his daughter's wedding, the Special Task Force teams shoulder the responsibility of investigating about the planned attack and suspected targets. While the teams unearth the findings from their investigation, they've less than an hour to stop the attack.
On a tragic day, as Sadhana and her younger brother, Vignesh, wait for their school bus outside their house in Coimbatore, unknown miscreants kidnap them. Worried, their parents file a complaint at the local police station. In the meanwhile, DSP Kadhir and team, who land up in Coimbatore, try to solve this kidnapping case.
After being kidnapped, Sadhana and Vignesh are made to believe they're being taken for a picnic. However, the kids start getting restless when their journey feels unending. In the meanwhile, Kadhir and team continue with their investigation and find some crucial clues that can lead them to the teenagers.
After the heinous murder of an aspiring actress, who is also the wife of a popular director, the Special Task Force team, led by Tamizh, springs into action. However, Tamizh is baffled when the press starts obtaining clues first-hand while the STF scrambles for any concrete evidence.
As the investigation continues, the case turns interesting. Tamizh finds it challenging to search for the head of the victim. Will he be able to identify the real murderer and solve the case, or does an unexpected twist await him?
In a mysterious case, two children are found dead and their parents are reportedly missing. As Kadhir and team continue their investigation, the clues lead them nowhere. In the meanwhile, a murder takes place in Yelagiri, the same place where Inspector Feroz is vacationing. Is there a connection between both the cases?
An intense investigation leads the STF to a suspect, and the team manages to rescue the missing couple. They rejoice thinking they have solved the complex case. However, their happiness is short-lived when they find another clue. Who is the real murderer?
Vinoth, a young cricketer, is found dead near his house. As word spreads, the news becomes the talk of the town. SP Vishwanath assigns the case to DSP Tamizh and his team, who manage to identify a suspect.
Tamizh and the team identify a suspect. But the case takes an unexpected turn, and the team loses all the case-related information. The situation turns worse after the officers realise that the person they suspect of the murder is, in fact, the victim.
Meera is found dead with her head buried in the mud and the rest of her body lying above the ground, making headlines. As Kathir begins his investigation, he finds out that the victim was injected with a deadly drug called Flakka. In the meanwhile, Meera's friend, Jinnu, gets kidnapped.
After Kathir finds out that Lavanya, Meera's friend, died unexpectedly before Meera, he lists the possible suspects and interrogates them. After narrowing down a suspect, he realises that the killer is going after all of Meera's friends. Will Kathir be able to save the girls?
A victim is found dead in a gruesome condition, grabbing the headlines and STF's attention. While the investigation reveals that the victim is a school teacher, Tamizh fails to obtain any clues related to the killer. Soon, another woman is found dead in a similar fashion, mounting the pressure on STF to nab the murderer soon.
As a thorough investigation begins, the STF discovers 10 similar murders in the past. After narrowing down on the culprit, they realise that there isn't any evidence to arrest the murderer. Tamizh devises a plan to trap the killer red-handed and takes a bigger risk that can pose a threat to his daughter's life. Will Tamizh succeed in capturing the murderer before the situation goes out of hand?
Sargunam, a middle-aged businessman, is found dead in his house under mysterious circumstances. After the STF takes up the case, they get to know that due to the lithium-ion particles found in his body, his death could have occurred due to pacemaker explosion. However, when a medical report confirms that Sargunam's pacemaker was intact, DSP Kadhir suspects foul play and begins his investigation.
The STF interrogates Varadharajan, Sargunam's brother, and finds out that Sargunam shared a great bond with his brother's family. The interrogation reveals that after Sargunam's wife passed away, Varadharajan had taken control of his entire business, making DSP Kadhir feel suspicious about the whole turn of events. Soon, Kadhir finds out the real culprit. Who is it?
After the body of Abhirami, a transgender, is found in a pond, the STF team decides to take up the case for investigation. However, the local inspector, Sarvam, picks up the case and expresses his disinterest in Tamizh's team resolving it. As both the STF and Sarvam work on the case simultaneously, Sarvam identifies 3 possible suspects and arrests them, much before the STF.
While the STF continues with its investigation and obtains fingerprints of the suspects from the crime scene, the team realises that there is a 4th accused involved in the crime. In the meanwhile, the 3 suspects arrested by Sarvam are found dead in prison. Will Tamizh and team be able to crack this unique case?
After Bharath, one of the leading exporters of Chennai, goes missing, his brother arrives from the US and files a missing complaint with the local police. Upset with the shoddy investigation, he seeks the help of the court in cracking the case. While the STF is entrusted with the responsibility of handling the case, renowned advocate Priya is assigned as the lawyer attracting enough media attention to the case.
As the investigation begins, the police locate Bharath's dead body. Despite the STF's best efforts, they fail to locate any evidence and the case reaches a dead end. In an interesting twist however, it is found that Bharath's assistant is also missing. Challenged by the turn of events, advocate Priya picks up the case and decides to solve it alongside the STF.
