Spring 1941. It is the third year of war, and when the siren sounds the people of Cambridge trudge to the city's public bomb shelters. Crowded, smoky, often raucous, the shelters have become a way of life for the poor. At dawn the body of a young man is found in a shadowy corner of the Trinity Shelter, one of three on the city's great open space - Parker's Piece.
Detective Inspector Eden Brooke searches the body and finds no wallet or papers,...