At Mathrubhumi, Anjali Menon, a diligent reporter, receives a letter from a man who signs himself as “Arjunan,” claiming to be the sole witness to the murder of former District Collector Firose Mooppan. The claim instantly grabs headlines and thrusts the mysterious Arjunan into a roaring media spotlight. As the story unfolds, Anjali faces escalating threats to her safety and that of her loved ones, prompting her to arrange a wary meeting with Arjunan with the help of Circle Inspector Sebastian, while the investigation is quietly steered by CI Stephen. The tension builds as a veil of secrecy surrounds the identity and motives of the witness, and the line between truth and rumor becomes increasingly blurred.
Meanwhile, Roy Mathew — an architect who has recently relocated to Cochin for a new job opportunity — shares a quiet moment with Anjali in a crowded café, a scene that the local press later conflates with the encounter that would change both their lives. Shortly after, Roy is attacked at his residence, and the police brief him as a possible Arjunan. Roy’s meeting with Dr. Ibrahim Moopan, the father of Firose, adds strain to the suspect’s image; Dr. Ibrahim challenges Roy to admit what he knows and to step forward honestly. With Anjali’s support, Roy aims to clear his name, and together they plan a cautious visit to Dr. Ibrahim’s home. The trip is cut short when they are ambushed en route, and they arrive to find Dr. Ibrahim dead. Although local authorities urge Roy to leave Cochin for his safety, he chooses to stay and fight for the truth.
As the investigation deepens, Roy realizes his phone is being monitored. He stages a calculated ruse to reveal the trackers and follow the trail to Aby Abraham, the Managing Director of City Mall. Alongside him is Thankappan, a diligent peon at the Collector’s Office, who helps them access blueprints for the abandoned Kochi Metro Rail project — a project that stalled in the wake of Firose’s death. The rediscovered plans suggest a troubling link between the metro route and government land, hinting that Aby Abraham and his circle may have had a motive to silence Firose. Roy begins to connect the dots and senses a larger scheme at play involving land, power, and a plan to derail any official inquiry.
Armed with new documents, Roy confronts Aby Abraham and reveals himself as Arjunan to force a reckoning. The confrontation takes a dramatic turn when Roy is kidnapped, but the trap is swiftly foiled by Sebastian and his team. Realizing Aby and his allies have betrayed him, Roy publically declares that he is not the true Arjunan, but a civilian who was pulled into the controversy by the media. He resolves to bring every shred of evidence to the public eye by presenting it before a panel of three judges, accompanied by the recorded confession and the documentation he has gathered.
With the stakes raised, the four business partners — Aby Abraham, Salim Memmen, Rajan Thomas, and Unni Natarajan — attempt a direct meeting with Roy. They lure him into Salim’s caravan, where they had previously murdered Firose, and try to silence him by forcing him to surrender his evidence. Roy, however, quietly tapes their confessions and captures the moment on tape, while also securing the necessary documents. He and his ally Jomy, Jomy, manage to overpower the conspirators and lock them inside the caravan, ensuring their plan cannot derail the forthcoming testimony.
On the day of the hearing, Roy steps forward to submit the documents and the recorded confession. He reiterates that he is not Arjunan but a regular citizen who was swept up in a public drama fueled by sensational reporting. The panel of judges receives the evidence, and the four culprits are taken into custody, their schemes exposed to the light of the legal process. Throughout the process, Anjali remains a steady presence, eventually handing Roy a letter from Arjunan that thanks him for his courage and persistence. The closing moments turn on a shared, knowing smile between Roy and Anjali as they confront the lingering mystery: Who is Arjunan?
