Towa serves as a guardian figure tied to the forest protected by Celebi in the fourth Pokémon film. She first appears as a young woman living near the forest entrance in Arborville. There, she encounters a boy named Sammy, warning him about the "Voice of the Forest" – a phenomenon linked to Celebi's time-travel abilities. She cautions that hearing it risks being spirited away to another time and gives Sammy a loaf of bread as a precaution. Forty years later, Towa reappears as an elderly woman residing in the same village. Accompanied by her granddaughter Diana, she continues her protective role, warning Ash Ketchum and his companions against entering the dangerous forest and echoing her earlier admonition to Sammy. When Ash returns with an unconscious Sammy, Towa recognizes Sammy as the boy she met decades earlier, identifying him as a victim of Celebi's time travel. Sammy, in turn, remembers her as the young woman from his past. Towa safeguards Sammy's sketchbook throughout the 40-year gap between his disappearance and reappearance, later returning it to him when he awakens in her home, bridging his past and present experiences. Following the defeat of the Iron-Masked Marauder, who survives a fall after his jetpack explodes, Towa confronts him alongside Diana, Mr. White, and the forest Pokémon. As the defeated Marauder pleads for mercy, claiming a misunderstanding, Towa observes, "I think the Pokémon understand perfectly," indicating her alignment with the forest's defenders. Her final appearance shows her bidding farewell to Ash and his friends.