Padmanabhan Master Nedumudi Venu and his wife Devaki wait for their only son Unni, Dileep, who has been missing for years. Ten-year-old Unni gets lost in the crowd during a temple festival where he went with their neighbour Panicker, popularly known as Poorappanikkar. Panicker’s daughter Ammu, Kavya Madhavan, shares the same anxious hope that her father will return one day with Unni. The master copies a hopeful image of what Unni might look like as he grows older, publishing a photo made by an artist in the newspaper, a quiet attempt to keep the memory alive.
Years pass, and the family finally locates Unni in Nagappattinam, bringing him back to the village. It soon becomes clear to everyone that Unni is not like other children; he behaves with the innocence of a small boy and stirs up all kinds of trouble, most famously by snatching mundu from people, turning daily life into a string of comic misadventures. He undergoes Ayurveda treatment under the gentle guidance of Fr. Stephen, while Ammu steps up to care for him with patience and devotion. Ammu’s cousin Gopikkuttan objects, because he harbors feelings for Ammu, and Panicker returns to the village, fueling tension as Gopikkuttan tries to turn Panicker against Unni.
Despite the complications, Ammu’s affection deepens into love for Unni, and she waits for the day of his full recovery so they can marry. A turning point comes during a confrontation with Gopikkuttan when Unni, in an act of protection, grips Gopikkuttan’s mundu to keep him from tumbling off a cliff. In that moment, Unni’s hidden past reappears: he is Vishnu, the son of Bangalore underworld gangster Maheswaran Thampi, a revelation that reshapes everything.
Vishnu rejects his father’s criminal world and pursues a life aligned with his own conscience. He falls for Gauri, an orphan girl Bhavana, and decides to marry her despite Thampi’s disapproval. Their friends arrange a secret party to celebrate, but Thampi’s men crash the gathering. In the chaos, Gauri is injured, and Vishnu loses his memory, slipping into a state of mental incapacity.
In the present, Thampi visits Vishnu and urges him to return home. Vishnu initially resists but agrees to go after Padmanabhan Master implores him to do what is right. Back at home, Thampi reveals that Vishnu and Gauri were punished for his own misdeeds, and that Gauri is not dead but bedridden. Before her death, Gauri wishes to see Vishnu and asks him to marry Ammu and bring her to Gauri’s side, a request that Thampi fulfills in a twist of fate. The final chapters see Vishnu marrying Ammu, as the village watches Krishnankutty [Harisree Ashokan], Unni’s friend and a village tailor, snatch his dhothi in a light-hearted close to the saga.
