The Interstellar Union Army officer Justice prepares to go to the Aoi Cosmos to capture and kill Elsie, whom he blames for destroying his life. Meanwhile, the Edens Zero crew arrives at Red Cave, surprised that the "fire planet" is an ocean-covered paradise. While relaxing at a beach, the crew witnesses a spacecraft crash into the ocean. Shiki's group investigates the craft and finds a human skeleton inside, with Rebecca noticing a message on the control panel reading "Nadia, love of my life". They also find a nearby underwater city littered with deactivated robots, along with a temple bearing a relief of Mother. After being attacked by a monster octopus, the group escapes into the waterless temple, where they are greeted by its guardian, an android woman named Nadia.