London, 1851 ... the Great Exhibition in the Crystal Palace is just opening. In this fourth follklore-infused comedy of manners, Mary Theadora Randolph, Countess of March, has travelled from rural Scotland for a delightful season in the City with her three seventeen-year-old wards ... nephew Jamie, niece Iris, and Lillith, daughter of her one-time friend Flora.
Thea simply wants a bit of a get-away from the farm, to explore the variety of wonders brought together in display at the Exhibition, and perhaps do a bit of general Londonish sightseeing. Too soon, she is wondering how such a lighthearted excursion could be turning out so complicated.
Almost upon arrival, Thea finds herself driven to the brink of outright rudeness by a social-climbing former schoolmate ... since Lillith is not at all what she seems, watching over her is an ongoing worry ... then without warning, half-Elfin nephew Willowisp must be added to the list of responsibilities ... arrogant German vampire-hunter Dr. Sunheitner keeps turning up wherever the Randolphs go ... and living in a rented flat overseen by a strait-laced, superstitious Irish landlady requires Thea's constant vigilance, to avoid revealing that they are anything but an ordinary Scottish family.
To top it all off, Thea finds herself suddenly involved with a passionate younger man ... a handsome American painter who seems to have almost as many secrets as Thea herself.