Gentlemen of Last Resort

In Nation's Britain (not our Britain, obviously) everyday affairs are controlled by Parliament, and the crown is worn by a King or Queen, but The Crown is maintained, and the really crucial decisions made, by the Gentlemen of Last Resort.

This is a secret society in the best narrative tradition: omniscient, omnipotent and totally secret. The members are known only by a color code for public communication. They exercise control through an "Old Boys" network including the military and make the bureaucracy go away when necessary to preserve the monarchy and the country.

When the King and the first 137 in succession to the British throne succumb to the Russian Influenza, they must return Henry Fanshaw to British soil to assume the throne.