One-named stunning actress Helen mysteriously vanished 30 years ago. An elderly family friend is unable to bear not knowing any longer and commissions Lady Frances Ffolkes to track her down. Taking on the role of Lady Sherlock, with her loyal maid Mallow drafted as her Watson, Frances finds herself immersed in the glamorous world of Edwardian theater and London's latest craze—motion pictures.
As Frances and Mallow make their way through the theaters, they meet colorful figures such as George Bernard Shaw and King Edward II. Tracking the theaters seems like a dead end. That is until one of Helen's old suitors is suddenly murdered. With the stakes raised, Frances and Mallow work quickly to uncover a box of subtle clues to Helen's whereabouts. But someone unexpected wants that box just as badly and is willing to kill to keep it shut.
The stage is set for murder and Frances and Mallow are determined to unravel the decades-old conspiracy in Death at the Emerald, R. J. Koreto's third installment in the captivating Lady Frances Ffolkes mysteries.