Year P.D. 323. Gjallarhorn's political intervention into the Arbrau central parliament escalated into an armed conflict using mobile suits. The incident was brought to an end by Tekkadan, a group of boys who came from Mars.

News of Tekkadan's exploits has also reached the ears of Wistario Afam, a youth born and raised at the Radonitsa Colony near Venus. Venus, which lost to Mars in the contest for development, is a remote frontier planet in which the four great economic blocs show little interest. It is now used only as a penal colony for criminals, whose inhabitants don't even have IDs.

Then Wistario, who hopes to change the status quo of this homeland, encounters a girl who claims to be the guide to the Urdr-Hunt.