Auriol differs from Ainsworth's other works because the action is presented entirely as a fantasy, so that the supernatural element (which also occurs in Guy Fawkes and Windsor Castle) is more prominent.

Indeed, the use of the phantasmagorical aspects of the story to create a nightmarish commentary on contemporary society of the 1830s and 1840s anticipates (in the early 19th century) the expressionism of Robert Wiene's Caligari.

He is injured by the warder, Baldred, and carried to the house of Dr Lamb, an alchemist and Auriol Darcy's grandfather, who is assisted by his faithful dwarf Flapdragon.

While he convalesces and falls in love with Ebba, the iron-dealer's daughter, Tinker and Sandman and their associate Ginger (a 'dog-fancier' who steals dogs and resells them) discover in the gentleman's pocket-book the private diary of a man who has lived for over two hundred years, and has committed nameless crimes.

Intermean (1800): Cyprian Rougemont visits a deserted mansion at Stepney Green, where he finds the portrait of his ancestor (of the same name), a Rosicrucian brother of the 16th century, one of the Illuminati.

There in a seven-sided vault lit by the ever-burning lamp and painted with kabbalistic symbols he finds the uncorrupt body with a book of mysteries, a vial of infernal potion, and a series of chests filled with gold, silver and jewels.

With use of the potion, he lures Auriol into a compact whereby he is given a magnificent mansion in St James's Square and £120,000, in exchange for a female victim whenever Rougemont requires one from him.