As he scavenges the Zalem dump heap for useful parts, cyberphysician Daisuke Ido comes across the remains of a female cyborg, who is still alive. Ido takes her home and decides to restore her, transferring her into a new cyborg body. Gally has no memory of her past, but soon displays remarkable fighting skills. She starts working as a bounty hunter and meets a young boy Yugo.

Together with Gally, Yugo tries to pursue his impossible dream of going to Zalem. A giant satelite floating above the city. Not realising that Yugo's dream can only end in missery, Gally sets out to help him.