As a component of the Psychotechnic League future history, "Un-Man" takes place in the year 2004, between "Marius" and "The Sensitive Man".

Politics in all countries - including the US - are polarized between "Pro-UN" parties seeking to integrate in this now global framework and "Anti-UN" ones promoting nationalism and sovereignty and sometimes resorting to violence in resisting the UN.

Robert Naysmith is a member of the United Nations Inspectorate, an international police force that neutralizes threats to world peace.

He then kidnaps and drugs a member of the conspiracy, learning that he has been assigned to assassinate Barney Rosenberg, a Martian colonist who is returning to Earth to retire.

Naysmith teams up with a Finnish Brother named Juho Lampi to rescue Rosenberg, and learns that he was a close friend of the original Rostomily.