London, 1864. Dr Felix Cowdrey is working in a London free hospital, and hating every minute of it. So many of his patients have illnesses and injuries that cannot be treated, and his inability to help them pains him deeply. Then he meets Dr Miles Wakefield who offers him a position at his private lunatic asylum in Essex. Intrigued by the opportunity to work with patients who have damaged minds rather than bodies, Felix accepts, and sets out for Flete House. Enjoying an early success with a female inmate, Felix believes he has finally found his vocation. But the return of a young woman to the madhouse's best bedroom sets Felix on a new path that will expose a shocking family secret and uncover a deadly conspiracy that will change his life forever.