The Man Who Was Thursday: A Nightmare is sometimes referred to as a metaphysical thriller.
In Edwardian era London, Gabriel Syme is recruited at Scotland Yard to a secret anti-anarchist police corps. Lucian Gregory, an anarchistic poet, lives in the suburb of Saffron Park. Syme meets him at a party and they debate the meaning of poetry. Gregory argues that revolt is the basis of poetry. Syme demurs, insisting the essence of poetry is not revolution but law.