Emeraldas, known throughout the galaxy as the Pirate Queen, travels through space on her heavily-armed ship, searching for a secret. Hiroshi Umino is a young boy who escaped the bounds of Earth only by building his own spaceship. He crashes on Mars, where he encounters Emeraldas, who sees a little of herself in the reckless young man.

The first new English translation of a work by sci-fi legend Leiji Matsumoto since 2003