Who killed Mr. Jessop? Who stole the Fellows necklace? Who attacked Hilda May? The web of suspicion encompasses a dealer in ‘hot goods’, respected jewellers, a millionaire, an ex-pugilist, a playboy, members of the nobility, a hard-boiled moll and a girl who could not forget her past. All the clues are there, as the indefatigible Bobby Owen works his way through a real peasouper of a London mystery and pierces the fog – displaying not only magnificent analytical powers but and admirable courage in the face of danger.