The primary social and cultural concern of The Avignon Quintet has to do with the quest for significance, for illumination which is simultaneously and necessarily physical, aesthetic and spiritual, in a world that is given over to darkness. The modern world, here centered on World War II, is seen as broken, inverted, far gone in madness.

The central symbol of the quest is the lost treasure of the Knights Templar, towards which the five volumes of The Avignon Quintet conduct the patient reader.

The madness of the modern world is delineated in a number of ways, but the fundamental premise, as expressed in Monsieur, concerns the failure "to face the bitter central truth of the gnostics: the horrifying realisation that the world of the Good God was a dead one, and that He had been replaced by a usurper — a God of Evil." Monsieur, the...