The British Union of Fascists was formed by Oswald Mosley in 1932; their members were called "Blackshirts" after Benito Mussolini's followers in Italy.

During the story, the Government decide on a moratorium regarding outstanding business debts, to prevent the London Stock Exchange failing; but this causes a run on the banks.

Kenyon Wensleadale, the Marquis of Fane, begins a relationship with Anne Croome, a secretary, after they meet on a train journey.

In London they have dinner at the Savoy Hotel; Kenyon, looking round the restaurant, "knew that this seeming prosperity was an empty, tragic sham.

[7] They are saved when Gregory Sallust passes by, and recognizes them; he is apparently a Brigadier General, in charge of troops in three military vehicles, one with a machine-gun, which is used on the crowd.

After a battle on board, there is a truce and Sallust's group are cast away on a small boat; after several days they come ashore at Shingle Street on the Suffolk coast.

Sallust's group, joining the inhabitants of Shingle Street, set up defences and make forays into the surrounding area, taking produce and stock from farms.

After a series of adventures, Sallust, Kenyon, Anne and Veronica are held prisoners in Ipswich where a local Communist government has been set up; they are sentenced to death as enemies of the State, after resisting an attempt to seize their supplies.

Waiting for execution, they switch on a radio and, for the first time in weeks, there is a broadcast: it is announced that the provisional Communist government that seized control in London during the crisis has been replaced by a reformed version of the Monarchy, headed by the Prince Regent.

Sallust, in danger of a court-martial for taking troops under false pretences, is pardoned in an amnesty for those who took criminal action during the crisis.