Miyuki Amaya (Kasumi Arimura) belongs to the sailing team of manned submersible research ship 6K (Shinkai 6500) at JAMSTEC (Japan Agency for Marine-Earth Science and Technology). She dreams of piloting the 6K. Her father was a pilot and a researcher, but died from a disease. Miyuki Amaya’s purpose is to research the deep-sea because her father told her about the deep-sea when she was little. Now, she is a cadet of the pilot.