Thittam Irandu

Athira, a Chennai cop, meets Arjun during a bus ride and feels an instant connection. They begin a relationship and soon decide to marry after some time.

The pair grows closer as their relationship deepens. They start talking about a future together and decide to marry after a period of dating.

Athira is drawn into the disappearance of her best friend, Deepa Surya, who was married to Kishore. Surya's car is missing, and a burnt car with a burnt female skeleton is found, kicking off the investigation.

The autopsy initially identifies the skeleton as Surya and suggests a freak accident. Athira remains unconvinced and suspects foul play may be involved.

Athira discovers Barani's fingerprints on Surya's burnt car, linking him to the case and tying him to another murder investigation. The evidence deepens the mystery surrounding Surya's death.

Barani admits that Surya and another murdered woman were his ex-girlfriends and that revenge was his motive. He claims a stranger in Surya's house thwarted his attack, and his fingerprints were left during a scuffle.

While Athira and Arjun's wedding plans progress, Athira remains preoccupied with Surya's case. New evidence prompts reexamination of Surya's corpse and the earlier conclusions.

Pathologists reveal that the victim is not Surya and that the accident was staged. The revelation exposes the earlier autopsy reports as fake, intensifying the mystery.

Kishore explains that Surya was forcibly married to him but loved another person. He orchestrated Surya's 'death' with friends and manipulated autopsy reports to protect the truth, showing Athira video proof of Surya living with her boyfriend but withholding their location.

Athira shows Barani the video of Surya with her boyfriend, but Barani says the man he saw in Surya's house is not the same as in the video. This contradiction points to the mysterious man being someone else, sharpening the plot.

Arjun reveals that he is actually Surya, a transgender man who loves Athira. Kishore explains the deeper history: Surya was always transgender and transformed into Arjun with support, a revelation that reframes everything.

Arjun asks Athira to accept his love as a man. Overwhelmed by the magnitude of the truth, she struggles and ultimately leaves without giving him an answer.

One year later, Athira and Arjun meet again, and she arrives with an answer to his proposal. The film ends on a note of uncertainty, leaving their future unresolved.