Why 1920s Paris Is the Best Setting for a Spy Thriller

Why set a thriller in 1920s Paris? This is the Paris of Hemingway and Fitzgerald, of Gertrude Stein and Nancy Cunard, of Josephine Baker in her banana skirt taking her pet leopard for a walk. This is a Paris of wild parties full of flappers and swells—surely this is not a place for spies, surely…