In May 1940, a disgraced young German captain (Jai Courtney) is appointed to Wilhelm's military guard in Holland, just after the Nazis have invaded. The Kaiser -- Germany's last emperor, still vilified by the Nazis for the country's post–Great War malaise — is living in exile there. Despite their animosity, the Nazis claim they want to spare from harm this key figure in the motherland's history, whom they believe is a prime target for British and Dutch spies.
The movie never delves too deeply into Wilhelm's complex opinions of the Reich -- he, too, held Jews accountable for the downfall of Germany, yet publicly decried the "shirted gangster" violence of the pogroms. But Plummer makes him fascinating and even sympathetic, a prideful monarchist incapable of grasping, even in his twilight years, that he's living hopelessly in the past.
Whenever Plummer is onscreen, The Exception is scintillating entertainment. Unfortunately, it gets bogged down in the rather lukewarm romance between the captain and a British, secretly Jewish spy (Lily James) posing as the Kaiser's maid, and on whether she will assassinate the Kaiser or defy orders and kill the far more deserving Heinrich Himmler instead. This storyline is never quite compelling, though the climactic chase scene is invigorating. And Eddie Marsan nearly steals the show as the salacious Himmler, who talks with relish -- and a mouth full of food -- of the practical reasons for exterminating children.