Thanks to the discovery of orichalt, a precious raw material, one can now transfer human consciousness into robotic "I-Machines". Unfortunately, there's a risk that the individual may become trapped in their metal body, unable to return to their original form. The Excavate Company, a group of daring I-Machine miners led by the infamous Grayman, is determined to harvest orichalt for profit, despite the inherent danger. While on a mining expedition, the team stumbles upon Maya Mikuri, a student who's been abandoned by her own group. Accused of taking classified information about orichalt by her former colleagues, Maya joins forces with the Excavate Company, hoping to clear her name. Together, they embark on an adventure that will change their lives forever. Among them is Ido, a team member, who's lost his memory, now given the opportunity to discover his true identity.