Police officers Adhi Narayanan, Kamal Haasan, and Abbas, Arjun Sarja, devise a bold plan to bring down a dangerous terrorist network. To do this, they deploy undercover operatives Anand and Shiva on a mission codenamed “Operation Dhanush,” tasked with infiltrating the group led by the Naxalite Badri and feeding back essential information to Abbas. The operation spans a year, but tragedy strikes when Anand is captured and chooses to end his life rather than be interrogated, leaving Abbas and Adhi with fragments of truth to connect the dots.
With Anand’s intelligence in hand, Abbas and Adhi deduce that the terrorists are about to strike at a high level, targeting a central government minister visiting their city. The hunt intensifies as security tightens around a pivotal rail hub in Tiruchirappalli. Adhi phones his wife at a public booth, a routine act that becomes a tense moment amid the looming danger. At the station, Adhi notices subtle, suspicious activity and probes deeper, but a sudden radio transmission—meant to guide their operations—alerts the terrorists and ignites a violent confrontation.
In the ensuing chaos, Adhi wounds a terrorist and prevents another from fleeing by puncturing a tire. The wounded insurgent staggers into the railway precinct, where Abbas finishes him off, and the car driver is detained for questioning. Adhi presses for information about Badri from the driver. The driver claims innocence, yet Adhi suspects a mid-level operative holds the keys to the plot. The terrorists reveal a chilling scheme to assassinate a minister who is about to visit the city, and an RPG shooter is brought in to carry out the hit. The minister is killed, and the shooter identifies the driver as Badri. Confronted with this revelation, Badri, using his influence, silences the imprisoned shooter.
A brutal hold is broken when Adhi defeats Badri but then chooses to interrogate him rather than execute him on the spot. Badri reveals a devastating twist: a spy has infiltrated their police department—Srinivasan, the mentor to Abbas and Adhi. Adhi alerts the authorities that Srinivasan is a double agent, but Srinivasan takes his own life before capture. Badri’s operations continue under a chilling new arrangement when Narasimham, Badri’s right-hand, sends terrorists who kill Adhi’s beloved dog and fatally wound Adhi’s son in a shocking display of power. Badri and Narasimham threaten Adhi’s family unless Badri is allowed to slip away, forcing Adhi to cooperate and effectively become a spy within his own force.
The collapse of trust compounds the tragedy: Abbas grows suspicious and shadows Adhi when he visits Badri. Badri catches and tortures Abbas to extract information, and the web tightens around the family of Abbas after Zeenath, Abbas’s wife, and their daughter seek refuge with Adhi and his own wife Sumitra. Sumitra [Gautami Tadimalla] becomes a pivotal figure in defusing the escalating danger as she intervenes in a confrontation with Surendar, one of Badri’s lieutenants, and eliminates him using her wit and resolve. Meanwhile, Mala, played by Anusha, remains under careful watch as the rebels maneuver to keep Adhi under their influence.
Consumed by guilt and the fear that he is becoming like Srinivasan, Adhi seeks to sever the dangerous alliance. He arranges a rendezvous with Badri, while Shiva—still in contact with Adhi—advises that Narasimham is meeting his wife, and if Narasimham dies, Shiva will ascend as Badri’s second-in-command. In a brutal confrontation, Adhi kills Narasimham and attacks Badri in a safe house, but he is overpowered. Surendar attempts an assault on Abbas’s daughter, and Mala is killed by Sumitra in a decisive act of protection. Adhi endures torture for information about Dhanush, his code name within the spy network, and the truth begins to fracture the fragile balance he has maintained.
Badri reveals a crucial disclosure: the group has recovered the radio that connects to the spy, confirming that Dhanush can no longer reach the police. The moment of truth arrives when Adhi realizes that Shiva—the ally he trusted—is actually Dhanush. Badri moves to kill Shiva, but Adhi breaks free, overpowers Badri, and kills him in a tense struggle. In a final, grim choice, Adhi orders Shiva to shoot him so that Shiva can preserve the espionage network. Shiva complies, shooting Adhi as Badri’s men burst into the room. In a chilling postscript, Shiva declares that Badri is dead, and that he will take over as the group’s mastermind. The mission is accomplished from a grim distance, but at the ultimate cost: Adhi and Abbas are honored posthumously for their sacrifices, leaving behind a legacy shadowed by loss and the uneasy paradox of duty versus loyalty.
