He suggests Gregory is not really serious about anarchism, which so irritates Gregory that he takes Syme to an underground anarchist meeting place, under oath not to disclose its existence to anyone, revealing his public endorsement of anarchy is a ruse to make him seem harmless, when in fact he is an influential member of the local chapter of the European anarchist council.

The central council consists of seven men, each using the name of a day of the week as a cover; the position of Thursday is about to be elected by Gregory's local chapter.

In order to make Syme think that the anarchists are harmless after all, Gregory speaks very unconvincingly to the local chapter, so that they feel that he is not zealous enough for the job.

[2] The literary critic Ian Fletcher notes that Chesterton's "Saffron Park", with which the novel begins, is a parody of the garden suburb of Bedford Park in Chiswick, with its red brick buildings, "the outburst of a speculative builder" (Jonathan Carr), "faintly tinged with art" (the suburb was considered aesthetic, and was home to many artists), and its Queen Anne architecture.

Chesterton's book allegedly inspired the Irish Republican Michael Collins with the idea "if you didn't seem to be hiding nobody hunted you out".

But the sense of mystery remains, heightened indeed by glimpses of the ordinary world, the backcloth against which the drama or melodrama or whatever we decide to call it takes place.

Definition remains impossible: The Man Who Was Thursday is not quite a political bad dream, nor a metaphysical thriller, nor a cosmic joke in the form of a spy novel, but it has something of all three.

Chesterton, a Protestant at this time (he joined the Roman Catholic Church about 15 years later), suffered from a brief bout of depression during his college days.

Producing a succession of wearisome polemics and mechanical paradoxes, he spent his life denying the vision that informed his greatest work.

[8]On 5 September 1938 The Mercury Theatre on the Air presented an abridged radio-play adaptation, written by Orson Welles, who was a great admirer of Chesterton.

[9] It was reported in January 1967 that Jerome Hellman and Arthur P. Jacobs' APJAC Productions were preparing movie projects including a musical adaptation of Chesterton's novel by Leslie Bricusse.

On Sunday 13 July 1947, the BBC broadcast a live theatrical adaptation by Cecil Chesterton and Ralph Neale, which was produced by Jan Bussell and starred Harold Scott as Thursday, Peter Bull as Sunday, Stringer Davis as Comrade Witherspoon, Arnold Diamond as Colonel du Croix, Richard Goolden as Friday, and Campbell Singer as Wednesday.

[11] A 90-minute adaptation was broadcast in 1975, dramatised by Ronald Barton and with John Samson as Thursday and Trevor Martin as Sunday.

The 2000 video game Deus Ex features several excerpts from the book and lists Gabriel Syme as a current resident of the "Ton Hotel".

The Council includes Gabriel Syme, Peter the Painter (Friday), and Newman's recurring character Kate Reed.