London, 1880. Kat Holloway, highly sought-after young cook to the wealthy of London, finds herself embroiled in murder when she’s accused of poisoning her employer, the loathsome Sir Lionel Leigh-Bradbury. Her only help as she works to clear her name comes from the mysterious Daniel McAdam, a handsome man-of-all-work who seems to know everyone and always happens to be in the right place at the right time.

Highly sought-after cook Kat Holloway takes a position in a Mayfair mansion and soon finds herself immersed in the odd household of Lord Rankin. Kat is fine with the family's eccentricities as long as they stay away from her kitchen, but trouble finds its way below stairs when her assistant is murdered. Afraid for her life, Kat turns to the mysterious Daniel McAdam for help. Daniel takes a position in the house as a footman and stand-in valet so that he can investigate covertly, but Kat cooks up a suspect list of her own.

December 1899. After the death of her beloved grandmother, Cleopatra Fox moves into the luxury hotel owned by her estranged uncle in the hopes of putting hardship and loneliness behind her. But the poisoning of a guest on Christmas eve throws her new life, and the hotel, into chaos. Cleo quickly realizes no one can be trusted, not Scotland Yard and especially not the hotel’s charming assistant manager.

Librarian Sylvia Ashe knows nothing about her past, having grown up without a father and a mother who refused to discuss him. When she stumbles upon a diary that suggests she's descended from magicians, she's skeptical. After all, magicians are special, and she's just an ordinary woman who loves books. She seeks answers from a member of the most prominent family of magicians, but she quickly learns that finding the truth won't be easy, especially when he turns out to be as artless as her, and more compelling and dangerous than books.

Frances Wynn, the American-born Countess of Harleigh, enjoys more freedom as a widow than she did as a wife. After an obligatory year spent mourning her philandering husband, Reggie, she puts aside her drab black gowns, leaving the countryside and her money-grubbing in-laws behind. With her young daughter in tow, Frances rents a home in Belgravia and prepares to welcome her sister, Lily, arriving from New York - for her first London season.