Berlin, 1938: Newly-appointed military attache Noel Macrae and his extrovert wife Primrose arrive at the British Embassy. Prime Minister Chamberlain is intent on placating Nazi Germany, but Macrae is less so. Gathering vital intelligence, Macrae is drawn to Kitty Schmidt's Salon (a Nazi bordello) and its enigmatic Jewish hostess Sara Sternschein, who is a treasure-trove of knowledge about the Nazi hierarchy in a city of lies, spies and secrets. Does she hold the key to thwarting Hitler?