September 1940. The height of the Blitz. When The Savoy advertises its series of underground shelters, a crowd of people from East London arrive at the hotel and demand entry. There they find a shelter worthy of The Savoy's clientele, but the next morning, after the air raid and when the Stepney protestors have left, it is discovered that one of the hotel's guests is dead, stabbed through the heart. Detective Chief Inspector Coburg and Sergeant Lampson are called in, and the finger of suspicion falls firmly upon the East Londoners, but not everything is as it seems in these sumptuous surroundings.