Unexpectedly, Grace finds himself next to an alien spaceship, where all but one of its inhabitants have died trying to also save their planet from the same threat. The ship's sole survivor, a rock-appearing figure Grace calls Rocky, teams up with the scientist to save their planets, launching a journey full of self-discovery, heartbreak, and at the root, a budding friendship that serves as an anchor to the film's ending when a tough choice needs to be made.