A dense yellow miasma swirls in the streets of London as Sherlock Holmes & Dr Watson accompany a beautiful young woman to a sinister assignation. For Mary Marston has received several large pearls
- one a year for the last six years
- & now a mystery letter telling her she is a wronged woman. If she would seek justice she is to meet her unknown benefactor bringing with her two companions. But unbeknownst to them all others stalk Londons fog-enshrouded streets: a one-legged ruffian with revenge on his mind --and his companion who places no value on human life...