The "Gem Warship" ("Hand Ship" in the model sheet) is a giant hand-shaped spaceship which made its debut in "The Return" and is the primary setting in "Jail Break".
The ship landed on the beach in front of the Temple, allowing Peridot and Jasper to capture the Crystal Gems and lock them in the prison cells aboard the ship in order to be taken to Homeworld.
The ship was utilized by Peridot and Jasper to head back to Homeworld with the imprisoned Crystal Gems and Lapis Lazuli, of whom they were potentially planning to destroy. Throughout the entire episode, the ship remains in orbit. However, once the Crystal Gems were freed by Steven and the ship's main core was destabilized by Garnet, the ship fell out of orbit and crashed. Peridot managed to escape through an escape pod and abandoned ship before the crash, and Steven bubbled the Crystal Gems, leaving Jasper and Lapis on the ship. The ship then blew up once on the ground (possibly due to the main core becoming unstable), leaving wreckage all over the Beach House and in the surrounding area. The thumb detached itself before the remainder of the ship was destroyed.