Salangui Hachyuping: Golaeboseogui Jeonseol

Romi and Heartsping are enjoying peaceful days together, but Romi's growing desire to choose her own path brings her into conflict with her mother, Queen Belita, over the responsibilities expected of her. Their disagreement takes a devastating turn when Belita disappears into the sea after a sudden incident.

Refusing to abandon her mother, Romi sets out across the ocean with Heartsping, the mysterious sea boy Kite, and three Teeniepings. Their search leads toward the legend of the Whale Heartstone, where the secrets beneath the waves may decide whether Romi can rescue Belita and understand what it truly means to follow her heart without turning away from those she loves.