
Gainer lives in a Domepolis in Siberia. One day, he is unexpectedly taken to a detention center by the Siberian Railway Guards on suspicion of emigrant activity. There, Gainer meets a young man named Gain and leaves with him when he escapes. They break into a manor house and Gainer steals an Overman to fight back against the Railway Police who have caught up with them.

Gainer Sanga, a skilled gamer, leads a normal life in the domed city of Yapan until he gets involved in a mysterious altercation, leading to the activation of an Overman.