In the Garden of Beasts: Love, Terror, and an American Family in Hitler's Berlin

No one could have done well as the US Ambassador to Germany in 1933, and no one wanted the job, except for William E. Dodd.  An academic who thought the posting would give him time to work on his history of the American South, he was completely unprepared for Hitler's Germany.  Dodd brought his family along, including his daughter Martha who became romantically involved with both Gestapo and Russian Communist officers.  Martha's personal story (Larson used her diaries as a primary source) dilutes the horror a bit, but I came away from In the Garden of Beasts admiring Larson's skill as a writer but too disturbed to have enjoyed the book.