It is March 1938. Hitler has marched into Vienna to a triumphant reception, but the 180,000 Jews living in the city fear the future. Katharine Simmons, an undercover SIS agent working at the British Passport Office, is distraught when her husband, also an undercover agent, is taken from their home and disappears without trace. Left alone in Vienna, Katharine's secret work prevents her from returning home, but the noose is tightening around the SIS operatives as a suspected double agent is betraying them. Can the love of a mystery man save Katharine from the Gestapo? Who is her secret betrayer? And what is the past that haunts her? In this extraordinary debut novel, love, honour and power compete against a backdrop of the growing tensions of 1930s Vienna.