At the Yercaud Police Station, a distraught complainant reports that his pregnant wife did not receive adequate medical care, resulting in a stillbirth. In a fit of rage, he reacts by assaulting the doctor responsible. However, the situation escalates when corrupt Assistant Sub-Inspector Basha intervenes, brutally attacking the complainant and imprisoning him instead. Shortly thereafter, the injured man is rushed to the hospital, highlighting the dire circumstances.
In a separate incident, Gautham, a cab driver who struggles with stuttering when under stress, becomes entangled in a road accident after colliding with a motorcyclist. Overcome with panic, he makes a desperate decision to conceal the fatally injured rider in his car’s trunk and hastily flees the scene, inadvertently leaving a significant piece of evidence behind – the motorcyclist's slipper. To evade the looming threat of murder charges, Gautham purposefully gets himself arrested for drunk driving and slaps Basha, a bold move to prevent a police search of his vehicle. Though Basha seizes Gautham's car, he plots to take revenge by confounding Gautham with false accusations of drug smuggling, albeit his fellow officers step in to thwart this plan.
The plot thickens with the tragic murder of Nivetha, a social activist dedicated to providing free education to children in the village. The S.P. directs the investigation officer, S.I. Nagaraj (Ajay Raj), to promptly resolve the case and also organize an awareness program concerning the prior tragic passing of a young girl child. At the police station, after discovering that Gautham had slapped Basha, Nagaraj decides to demean Basha by making Gautham sit on a stool, stirring Basha’s ire. The investigation takes a turn when Rathinam and his wife arrive to discover that their daughter, Nivetha, is the murder victim. Meanwhile, Gautham, overwhelmed by the emotional toll, retreats into the restroom.
As tensions rise, Basha mocks Nagaraj, questioning his capability to crack the case. Nagaraj retaliates, humiliating Basha further by ordering him to serve tea to Gautham. During the ongoing investigation, the police delve into the CCTV footage from a nearby petrol pump and eventually identify the killer of the biker as being linked to Nivetha’s death.
Possessing a chain that belonged to Nivetha, Gautham employs it as a bribe to Constable Sundaram (Bava Chelladurai) to retrieve the killer-biker's phone and discreetly exchanges it with his own. The police make headway in their inquiries by tracing the bike to Balu, and Basha employs coercive tactics on Balu's wife to obtain a confession. In a critical moment, Constable Vikas (KPY Sathish) presents the slipper that Gautham had forgotten, and Balu's son identifies it as belonging to his father, further complicating the narrative.
As the investigation progresses, the scene becomes more tense as the police note that the hit-and-run took place at a specific location, with a broken headlight acting as a distinctive mark. Upon hearing this over the walkie-talkie, Gautham smashes his own car's mirrors and headlights in a panic. Meanwhile, Basha finds Gautham's wallet, but Nagaraj grows suspicious of Basha, wondering if he is trying to frame Gautham. In a desperate ploy, Gautham pretends to have an epileptic seizure, injuring his leg to align with blood stains found on the floor. Eventually, Nagaraj orders Gautham's release, but not before Sundaram demands a hefty bribe of ₹25,000.
Gautham is sent to an ATM for the bribe where he cunningly switches on the confiscated phone and gets effortlessly tracked by Nagaraj. In a clandestine inquiry, Nagaraj manages to gain Gautham's trust to obtain the phone, but then betrays him by framing him as Nivetha's murderer. As events unfold, it is uncovered that Nagaraj was indeed the mastermind behind Nivetha’s murder, having received assistance from Balu (Jeeva Ravi). Unfortunately for them, an incriminating audio clip from Balu's phone lands in Basha’s hands.
The courtroom drama escalates when Inspector Anand takes charge of presenting Gautham in court. During a press conference, Gautham stuns everyone present by revealing Nagaraj’s complicity in Nivetha's untimely death and attempts to hand over her phone to the media. As Nagaraj tries to seize the phone, Anand steps in to arrest both Nagaraj and Gautham. Gautham discloses to Nagaraj that the phone he passed to him was his own, subverting Nagaraj's schemes.
Flashbacks unveil the dark truth that Nagaraj caused a hit-and-run accident resulting in the death of a young girl tutored online by Nivetha. In a drunken state, Nagaraj had recklessly run over her with his jeep, coercing her parents due to his police status, yet it all was recorded on Nivetha’s phone. Gautham finally confesses to having intentionally killed Balu, while simultaneously sending the incriminating video to Basha.
The live video Gautham releases to the press, accusing Nagaraj, quickly goes viral, leaving the latter with no escape route as he ultimately faces arrest. Even as Nagaraj attempts to pin the blame on Gautham for Balu's death, Basha produces evidence against Nagaraj through the wallet found. Due to insufficient evidence, Gautham is released from custody, but the story unfolds tragically as it becomes known that Nivetha was Gautham's sister. In a heart-wrenching conclusion, the family is engulfed in sorrow as they receive her body from the mortuary, marking a profound and painful chapter in their lives.
