Against Pearl's wishes, Steven becomes determined to get stronger after watching Garnet and Amethyst fuse into the mighty Sugilite.

Steven needs a musical partner for an upcoming show, so he uses a time travel device to recruit himself as the perfect bandmate.

Lapis Lazuli disappears after reigniting a past conflict with Garnet, Amethyst and Pearl, and takes the ocean along with her, leaving Beach City in a panic on the first day of summer. Steven, Connie, Greg, Lion and the Gems go on a mission to confront Lapis and set things back to normal.

Connie tells Steven the story of how she, Peridot, and Lapis attempted to take the Crystal Gems' places as the protectors of Beach City while he was in space.