Sora tells Leon about the Keyblade closing the Keyhole of Wonderland. Leon informs Sora that, according to Ansem's reports, each world has a Keyhole that leads to the heart of that world. He explains that the Heartless are attempting to steal those hearts and that they appear whenever darkness enters the heart. When the world's heart is stolen, then the world will be destroyed. He tasks Sora with visiting different worlds and sealing their Keyholes with the Keyblade, telling him that he's the only one who can do it. Sora is hesitant, but is encouraged by a woman who Leon introduces as Aerith. She hands lemonade to the group and informs them that she asked Cid to repair their Gummi Ship. Sora remembers about the gummi block they acquired and asks about it, but is told to ask Cid with the claim that he should know.
In the Accessory Shop, Cid identifies the gummi block as a navigation gummi and plans to install it on the ship while he's repairing it. While he is doing that, he asks the group to deliver an old book to an old house past the Third District.