Upstairs. Downstairs. New maid Jane Wilbred, daughter of a hanged murderess, takes a position in the Bentley household, suitably subdued by her former employer, a mean-spirited woman who demands servants understand their place in the natural order of society. With few expectations, Jane slips into a routine that is demeaning and soul-killing, the strict servant caste system designed to support the ruling class.

In this particular household, where elderly Mrs. Bentley has been felled by a stroke, the son, Robert, returns to London in 1893 with his sophisticated wife, Mina, who is distressed at leaving France for the duties awaiting her, out-of-control servants and a city with little to offer compared to Paris.

Reluctantly, the second Mrs. Bentley takes up her duties, much to the consternation of the help, her husband increasingly involved with an all-consuming interest in the “science” of anthropometry - identifying criminals by body measurements. Much like phrenology, anthropometry is yet another attempt to quantify criminal tendencies through scientific measurement, an innovative concept on the cusp of a new century.

Fingerprinting has also come into favor, but unlike Robert’s passion, this technique will remain part of the technical lexicon. Much to his wife’s dismay, Robert is hopelessly enamored with his work in anthropometry, leaving her to deal with a failing mother-in-law and a group of unruly downstairs employees who view her as an interloper. Blissfully unaware, Robert dedicates himself to his work in hopes of making their fortune, Mina increasingly encumbered by her responsibilities and resentful at having to live in London.

The contrast between Jane, the new maid, and Robert’s wife is provocative. Mina sees a cleverness in Jane that may or may not exist; Jane feels put upon, confused by her new mistress’s expectations as the most recent hire. But there is more to Mina than first appears, secrets she has not shared with Robert that now threaten to unravel her marriage. Without the authority wielded by the incapacitated elder Mrs. Bentley, Mina seems not to be taken seriously, relying on Jane to spy on the other servants in an unmanageable household.

Events conspire to turn the Bentley home into chaos, two deaths, one unexpected, and the arrival of a widow to lay claim on the family. Through it all, the author skillfully manipulates her characters: naïve Robert; anxious Mina, who longs for the safety of Paris; a bizarre group of servants jostling for advantage; and an old foe come to destroy Mina’s fragile house of cards.