When a woman is murdered at mystery writer Henry Loureoux's apartment, Scotland Yard inspector Dunbar begins his investigation with a note that the woman left behind written to a Mr. King. When M. Gaston Max, a Parisian criminal investigator and master of disguise, comes to help the case, things begin to get interesting. Can they find out who Mr. King is and stop the crazed murderer from striking again? Can they find Henry's butler, Soames, before he ends up in danger? And where is Henry Loureoux's wife? This book has a lot of "Yellow Peril" and other racial stereotypes, typical of its day. The novel was the basis for the 1921 British silent film The Yellow Claw. (Summary by TriciaG)