Taking place in 1942 in occupied France, Richard Quintain is working with a small group of demoralized partisons trying to stop a Panzer advancement. And somewhere in the group is a double-agent, telling the Germans their every move.
Specializing in action noir, William Arthur Howard Baker got his break writing for the Sexton Blake series of detective thrillers in the mid 50's, eventually becoming an editor. He reused many of the plots from this popular set of stories for his own spy series. A penname of his was Peter Saxon.