The Fatherland Files by Volker Kutscher
July 1932. When a drowned man is found in a freight elevator in Haus Vaterland, the giant pleasure palace on Potsdamer Platz, Inspector Gereon Rath is called in to investigate. It's not that Rath hasn't problems enough. His hunt for a mysterious contract killer has been stalled for weeks, and his on-off lover, Charlotte Ritter, has just begun her probationary year with Berlin CID. The corpse in Haus Vaterland looks to be part of a series of murders whose trail leads eastwards to the Polish border - and beyond.