To "open up" a play for film means to expand the action beyond whatever limited settings were presented on stage. (Edward Albee famously hated how Mike Nichols opened up Who's Afraid of Virginia Woolf?, for example.) Volker Schlöndorff's Diplomacy, based on the play by Cyril Gely, is mostly just two old guys in an admittedly opulent room: Gen. Dietrich von Choltitz (Niels Arestrup), the military governor of occupied Paris in 1944, under orders from Hitler to blow up Paris out of spite for it not getting as pounded as Berlin; and Swedish consul general Raoul Nordling, who sneaks into von Choltitz's office via secret passageway (complete with a bookshelf door) in order to convince him to not blow up Paris. It's based on a true story, and since specific targets like the Eiffel Tower and the Louvre are still standing we know that Nordling was successful in his task, but how they reach that point is still plenty compelling. For better or worse, though, Schlöndorff opens up Diplomacy and often shows us what's happening outside. It's the final night of the Liberation of Paris, so there's plenty to see, particularly the French Resistance battling Germans under the city, but it's not strictly necessary, either. Sometimes two people deciding the course of history is enough.