In the Garden of Beasts by Erik Larson (Author)

A mild-mannered professor from Chicago, Dodd brings along his wife, son, and flamboyant daughter, Martha. At first Martha is entranced by the parties and pomp, and the handsome young men of the Third Reich with their infectious enthusiasm for restoring Germany to a position of world prominence. Enamored of the “New Germany,” she has one affair after another, including with the suprisingly honorable first chief of the Gestapo, Rudolf Diels.