Whilst Lord Marley prepares for the important Derby he is hosting at his large country estate Marley Chase, located near London, his lady wife is in the midst of readying their sumptuous mansion for the onslaught of house guests set to arrive to take part in the festivities surrounding the horse races. Frantic that she’ll not be ready in time, Lady Marley has recruited Miss Abbott’s help in assembling a prestigious art gallery in her home.
Whilst gathering precious artifacts to display in her ladyship’s gallery, Juliette comes upon one of Lady Marley’s house guests bludgeoned to death! When a valuable ruby ring is discovered missing, the finger of guilt points squarely at her! The brutal murder and a rash of thefts render all the house guests, most especially the ladies, paralyzed with fear. Because Miss Abbott’s handsome gentleman friend Mr. Sheridan is also on the estate, having been dispatched to protect a visiting statesman from an assassin bent on killing him, he and Miss Abbott spring into action to run the killer to ground before he strikes yet another deadly blow!