In the fourth installment of Imogen Robertson’s acclaimed historical suspense series, Mrs. Harriet Westerman and Gabriel Crowther depart England for the Duchy of Maulberg on a desperate mission to save a man accused of murder.

Shrove Tuesday, 1784. As Germany’s elite dance at a masked ball, the beautiful Lady Martesen is murdered. Daniel Clode, Mrs. Westerman’s brother-in-law, is found near the body, his wrists cut, his memories nightmarish. Is Daniel a killer? As he awaits execution, Westerman enlists Crowther, the increasingly reclusive anatomist, to help prove Daniel’s innocence. After another ruthless death, the investigative duo find themselves racing to solve the mystery behind the killings—but no one will talk, and the clock is ticking for Daniel.