Night falls in London, and a London particular pea-souper fog envelops the city. In Maida Vale, Rose and her family doctor Tedwards race through the dark after a man has telephoned claiming that he has been struck by an assailant in Roses house. Arriving after an achingly protracted journey through the impenetrable fog, the victim, Raoul Vernet, is dead. The news which he had brought from Switzerland for Roses mother, was never delivered.
