Lud-in-the-Mist begins with a quotation by Jane Harrison, with whom Mirrlees lived in London and Paris, and whose influence is also found in Madeleine and The Counterplot.

In the novel, the prosaic and law-abiding inhabitants of Lud-in-the-Mist, a city located at the confluence of the rivers Dapple and Dawl, in the fictional state of Dorimare, must contend with the influx of fairy fruit and the effect of the fantastic inhabitants of the bordering land of Faerie, whose presence and very existence they had sought to banish from their rational lives.

[1] Whereas in the novels Madeleine and The Counterplot, Mirrlees adapted elements from history, religion and literature, her use of a secondary-world setting in Lud-in-the-Mist associates it with the tradition of high fantasy, and thereby with its current popularity.

[6] David Langford and Mike Ashley describe Lud-in-the-Mist as "a moving book, shifting unpredictably from drollery to menace to a high poignancy that sticks in the mind".

He described Mirrlees's writing as "elegant, supple, effective and haunting: the author demands a great deal from her readers, which she repays many times over.