University student Weyn lives in Bangkok with his mother, Sasivimon (Mon). Though his life appears comfortable, he quietly struggles with the absence of his late father and a sense of emotional suffocation. One day, Weyn accompanies his mother, a drama director, on a location scout to the countryside. When their car gets stuck in the mud, they seek help at a nearby house—where they meet Inthawut, a close friend of Weyn's late father.

The next morning, Weyn is moved by Inthawut’s gentle nature. The two begin to bond. When Mon finally appears, tension returns. Still sulking from the night before, she leaves for town after Weyn sincerely apologizes. Alone, Weyn helps Inthawut build a bridge—and becomes captivated by the older man's strength and presence.

Mon prepares to leave for an award ceremony, skipping Weyn’s 20th birthday party. She confides in Inthawut, asking him to guide her son. Meanwhile, Weyn wanders alone, feeling a subtle but profound shift on this seemingly typical birthday. He clutches a keepsake from his father and crosses the river into the forest—toward something new.

With Mon back in Bangkok, Weyn and Inthawut are alone. Over wine, Inthawut reminisces about Weyn’s father, Siam. However, when the story touches on how Mon and Siam got together, a shadow falls across Inthawut’s face. Weyn presses for the truth about his father's past relationships, and Inthawut—clearly in pain—admits he abandoned Siam. Weyn gently wipes away his tears.

Weyn and Inthawut watch Mon give a witty award speech on TV. Later, Weyn presses Inthawut to continue last night’s story. Inthawut reveals that after Weyn’s birth, Siam’s buried feelings and alcoholism took hold. Regretful, Inthawut laments his own cowardice. Weyn, shaken by what he’s learned, confesses his love to Inthawut.

Mon returns home with her trophy. Weyn questions Inthawut about what he should learn from life—and is struck by the answer. That night, as Mon rambles on about her award, Weyn mocks her, and Inthawut tries to mediate. Observing their interaction, Mon senses something new between her son and her old friend. The next morning, Weyn reveals his feelings to her, leaving Mon deeply shaken.

Late at night, Weyn drives off in the rain. Fearing her son is doomed to repeat her ex-husband’s fate, Mon lashes out at Inthawut. When Weyn returns and goes straight to Inthawut, Mon quietly walks away. Later, as Weyn comes to her, Mon tearfully begs him to return to Bangkok. Weyn gently takes her hand and says, “Let’s talk tomorrow,” then leaves the room.