Ramachandran aka Ram is a travel photographer. He visits his high school and is overcome by memories. A reunion is arranged through their school WhatsApp group. At the reunion, his friends Murali, Subhashini and Sathish catch up with him. Murali hesitantly mentions that Janaki aka Jaanu (Ram's childhood love) is coming from Singapore.

In 1996, Ram and Jaanu have been friends and classmates in 10th grade. Jaanu is a talented singer. Ram develops feelings for Jaanu and she reciprocates. Once their board exams are over, they have a moment with each other where Jaanu asks him not to forget her until they meet again after the holidays.

Back in the present, Jaanu arrives at the reunion and searches for Ram. When Subha points Ram to her, Jaanu walks towards him. She reminisces the first day of 11th grade when she eagerly awaits Ram's arrival to the classroom, but he doesn't show up. She finds that Ram has left the school because his father had financial difficulties and his family relocated to Madras overnight. Jaanu is inconsolable and pines for Ram until she completes school.

Ram and Jaanu finally meet and find it uncomfortable to interact with each other, but gradually get along. Their friends talk about Jaanu's married life in Singapore and disclose that Ram is still single and hasn't moved on. After the reunion party, both go out on a drive. Jaanu reveals how she could not forget Ram and would have traded anything just to have met him once back then. She narrates how circumstances forced her to marry someone else. Then, Ram asks Jaanu if she really doesn't remember the day he came to her college to meet her. Ram says that he and Murali waited in front of Jaanu's college to meet her and passed on a message through a student. Surprisingly, Jaanu refused to meet Ram and forbade him to contact her again. He returned sadly and never tried to meet her since then. Jaanu is devastated after listening to this and reveals that she never saw them at her college and thought it was her stalker who was troubling her. Ram tells that except for the mistake of assuming that she hated him, he knew everything about her life. He also tells about seeing her from afar at her wedding. Jaanu is heartbroken because she felt his presence and expected him to come for her until the last minute. Both feel sad about their misfortune and finally, come to terms with everything that happened in their lives. Jaanu expresses her desire to spend the final few hours with Ram before she catches the flight back home.

They go out into the city and then to a restaurant and catch up on more memories. There, they meet Ram's photography students who assume Jaanu is his wife and request her to share their story. Jaanu obliges and narrates an improvised version of the time when Ram tried to meet Jaanu at her college. She tells about how they finally met and made up and have been together ever since and got married. Albeit feeling awkward, Ram tries his best to play along. The students leave and Ram asks Jaanu to visit his apartment as it is already late at night. On the way, they get drenched in the rain and Ram gives Jaanu some of his dry clothes.

At his apartment, Jaanu is visibly upset that Ram doesn't have a love life and requests him to move on and get married and have a family. She finally sings Ram's favourite song for him, a song that she had purposefully avoided singing in school in spite of his repeated requests. Ram shows Jaanu a collection of their old memories like love poems, dried flowers, and their school uniforms. They realize that time is running out and go back to Jaanu's hotel to get ready for her flight in a few hours. Jaanu is sad knowing that she'll leave Chennai and Ram very soon. At the airport, Ram escorts her to the boarding gate and they bid a teary farewell. Jaanu then gets into the flight and leaves.

Back at his home, Ram finds Jaanu's clothes that he had put to dry the previous night. He folds them neatly, puts them along with his treasured collection of school memories, and shuts the suitcase as the film comes to an end.