Lord Anthony Blake, a former spy for England, finds himself at loose ends after the fall of Napoleon. Genteel widow Alicia Carrington, who's in London to chaperone her younger sister, puts an end to Anthony's ennui when she stumbles upon a dead body at a soiree and he stumbles upon her at the same time. A mysterious villain seems determined to frame Alicia for the murder, but the real danger lies in the secret she's hiding from everyone-including Anthony, who quickly insinuates himself into her life.