It centers on Wehrmacht Captain Stefan Brandt (Jai Courtney) assigned to protect exiled Kaiser Wilhelm II (Christopher Plummer) in occupied Holland, where he begins a passionate affair with maid Mieke de Jong (Lily James), who reveals she is Jewish. The plot follows espionage, Himmler's visit, and Brandt's choice between duty and personal morality, with the title referring to Brandt as a 'decent' German amid Nazis.

The story remains a traditional historical romance and espionage tale without any modern activist framing or identity politics injected into the premise. Casting matches historical roles without any race- or gender-swapping of established figures, and the Jewish identity of Mieke drives personal stakes in the forbidden affair but stays organic to the source novel and the WWII era rather than serving as a vehicle for contemporary messaging. Director statements focus on moral choices and colliding Germanies instead of systemic oppression narratives or DEI mandates. Reception shows mixed historical critiques but no woke discourse or casting controversies, confirming the film's avoidance of progressive ideological overlays.