Switzerland’s strange postwar burden of quasi-collaborator-guilt, with all its symptoms of evasion and denial, is the theme of this intimately presented black-and-white movie from writer-director Laurent Nègre. It is inspired by the real-life case of Hans Frölicher, the Swiss ambassador to Nazi Germany from 1938 to the end of the war, much approved of by the Nazi elite due to his submissive pro-German loyalty. It is also a free adaptation of The Envoy, Thomas Hürlimann’s stage-play on the same subject. Michael Neuenschwander plays the ambassador, here fictionalised as Heinrich Zwygart; he returns to Switzerland and his handsome family estate in...