Switzerland, 1868. Resolute variety hall actress Ophelia Flax has spent the last several months performing in a traveling circus, settling into the gritty camaraderie of circus life, and—almost, anyway—forgetting all about Professor Penrose, love, enchantment, and bunkum generally.

When Ophelia breaks her arm in a trick pony-riding accident under the big top, she is whisked away by a guilt-ridden benefactor to convalesce in the Waldsanatorium, a grand hospital perched high over a valley. Soon after her arrival, she discovers that one of the patients, the young American Imogen Melchor, is trapped in a morbid lethargy from which she cannot be woken and which—so her parents insist—was caused by the prick of an enchanted spindle.

Ophelia is not one to twiddle her thumbs, even though she's discomfited by the sudden reappearance Professor Penrose, whose head is turned by rumors of magical spinning wheels. Inquiring together into Imogen's plight, they uncover a wicked plot concerning medical theories, a pagan goddess, and a contested will . . . and, along the way, perhaps reawaken their own slumbering hearts.