On a stormy night, Dr. Anand, a highly respected physician, finds himself caught up in a mysterious series of events that unsettle his very sense of reality. While traveling during heavy rain, he encounters a strange woman who introduces herself only as No one, and she requests a lift. As soon as she gets into his vehicle, an eerie silence falls—the windshield wipers mysteriously stop functioning, creating an unsettling atmosphere. The woman then guides him beyond what seems visible, leading him outside a cemetery where the gates open on their own, and he hears haunting singing: "Nanae Varuven meendum varuven". This chilling scene marks the beginning of a series of supernatural occurrences that blur the line between reality and the unknown.
Dr. Anand is on the brink of inheriting a significant estate from a distant relative, but there's a Catch—he must prove that he is completely mentally stable. Any sign of insanity, given his family history of mental illness, could cost him both his inheritance and his reputation. Meanwhile, his professional colleague, Dr. Lata, harbors feelings for him, but Anand is already involved with his girlfriend Rama. A complex love triangle intertwines with the unfolding mystery, as the death of Rama by cyanide poisoning raises suspicions. Her murder prompts police investigations, placing Dr. Giri, her father and chief hospital doctor, under scrutiny as a potential suspect.
The plot thickens when Anand is called to a remote, dilapidated mansion on a stormy night, where he finds the supposedly deceased girl from earlier has mysteriously reappeared, despite the mansion being abandoned and rumored to be haunted. The police reveal that similar incidents have repeatedly taken place over the years—particularly on rainy nights—and that multiple doctors have registered descriptions of encountering this girl, who was supposedly killed in a tragic rail accident long ago. Anand's frustration deepens when he sees a newspaper confirming her death in the rail disaster, adding to his confusion.
Despite his sorrow over Rama’s death, Anand's life takes an unexpected turn when he becomes engaged to Sandhya, a woman his mother introduced as a suitable match. However, during their wedding night, Anand is shocked to discover that Sandhya bears an uncanny resemblance to the girl he's been haunted by, leading him to avoid her out of fear and suspicion. His suspicions intensify when he notices Sandhya painting the very bungalow where he had encountered the mysterious woman. Soon after, he hears her singing parts of the haunting song again—confirming her connection to the supernatural presence.
Further bizarre incidents include Sandhya reaching the hospital and attempting to seduce Anand with her beauty and singing, and an uncanny scene where Anand and Sandhya sit in his car during a foggy, stormy night, with the wipers mysteriously stopping once more. He even takes her to the same bungalow, where she vanishes from his sight, only to appear again waiting for him at home. His mother insists she has never left the house, deepening the mystery. Desperate for answers, Anand arranges for Sandhya to leave by train, but shortly after, he learns her train was involved in a terrible accident—yet he still sees her on the terrace that very night, further pushing his mind into chaos.
Seeking clarity, Anand journeys to Shimla, where a wise monk on a hilltop explains the tragic history of the area: a young girl who fell and died while romancing her lover over a hundred years ago. The monk reveals that her ghost has been wandering ever since, searching for her lost love—who has been reincarnated in Anand himself. This revelation shocks Anand as he catches sight of Sandhya again, singing the final part of their haunting song, "Nanae varuven meendum varuven". Motivated by this understanding, Anand attempts to confront her, but as he follows her through the old bungalow, he witnesses a sequence of surreal and terrifying sights where Sandhya appears and disappears, and a duplicate of her appears to claim she is the real Sandhya.
The climax unfolds dramatically when Anand confronts the woman on the roof, only to see her fall tragically to her death. From the shadows emerges Ramesh, Anand's cousin, who reveals a sinister plan: everything was orchestrated by him from the start to make Anand appear mentally unstable, so that his inheritance would pass to Ramesh. A violent confrontation ensues, with hired henchmen attempting to eliminate Anand. Just in time, police officers arrive and arrest Ramesh and his accomplices, bringing the schemes to an end.
In the aftermath, the police officer explains the truth behind the strange events: the entire series of acts was meticulously staged by Ramesh and his associates—using the policeman, a monk, and a servant named Madhav—who fabricated the appearances of the ghostly woman, the mansion, and other supernatural phenomena. The story of the other girl, Sandhya's twin sister, is uncovered: her mother had separated the twins when they were children, and she grew up unaware of her sibling’s existence. The twins’ mother passed away, and her father only uncovered her whereabouts years later. Ramesh discovered her existence and devised a scheme to exploit her situation.
The story concludes with a resolution that unites Sandhya and Dr. Anand, revealing that Sandhya was not a ghost, but the victim of Ramesh’s cunning plans, manipulated into appearing ghostly through staged illusions. The duality of her identity, the twin sister hidden away for years, and the conspiracy behind her death are finally unveiled. With the mystery resolved, Anand and Sandhya embrace, signifying the triumph of truth and love over deception and supernatural fear.
