Komagan, Gautham Vasudev Menon is a leading advocate in the Madras High Court and the estranged youngest son of retired justice Ramanathan, a rift that began a decade earlier when Komagan defended a criminal Ramanathan had convicted, sparking a heated argument that ended with Ramanathan slapping him. Years later, Ramanathan publicly apologizes at his birthday party. Later, he discovers a 13-year-old letter from Amudhavalli, Ramanathan's former lover, revealing that she has a daughter named Kanmani, who was imprisoned in Madurai. He sets out to find her without informing his family.
On his journey to Manamadurai, Ramanathan realizes that he had sentenced Kanmani, who was then an inspector, to life imprisonment for being involved in a shootout that killed three criminals. He also learns that Kanmani lived with her mother and an adoptive father named Murugan and proceeds towards Rameswaram in search of Kanmani and Amudhavalli. Meanwhile, Ramanathan's family begins searching for him, and Komagan is blamed for Ramanathan's disappearance.
Veeramani, Yogi Babu, a hotel owner in Kumbakonam, is separated from his daughter Saaral, who is being cared for in a juvenile home in Rameswaram, where Kanmani, now a social activist and warden, looks after her. Unbeknownst to Veeramani, Kanmani is Ramanathan's daughter. Veeramani helps Ramanathan after he loses his wallet. At a conch factory, Ramanathan recognizes Kanmani and also meets Meena, Veeramani's acquaintance and Saaral's mother, Meena, Meenal. Veeramani reunites with Saaral at the orphanage, but their attempt to leave together sparks an issue. The police intervenes, but Ramanathan's timely arrival resolves the situation.
Veeramani shares his past with Ramanathan, explaining how he helped Meena when she was pregnant and fleeing her cheating ex-husband, Sethu. A few months later, Sethu returned, so Veeramani had to send Meena and Saaral to Sivagangai. However, Sethu's abuse prompted Meena and Sethu's sister to seek refuge in the orphanage. Ramanathan, moved by Veeramani's kindness, helps reunite him with Saaral and ensures Sethu's arrest.
Ramanathan confesses his paternity to Kanmani, but she refuses to forgive him for abandoning her mother. Kanmani reveals that her mother took responsibility for the family, pretending to act like her father Murugan to protect their family. Komagan searches for Ramanathan through his friend Badri, discovers Amudhavalli's connection, and finally meets Kanmani at the orphanage. He asks for forgiveness on his father's behalf and acknowledges Kanmani's newfound family. However, Ramanathan, who is overwhelmed by guilt, leaves the orphanage and is seen gazing at the ocean. Meanwhile, unable to find his father, Komagan regrets taking the case that drove him and his father apart for more than a decade.
