12 Angry Men. My Dinner with Andre. Steve Jobs (a stretch, but much more a play than a movie). There's some play adaptations which have few characters and most

12 Angry Men. My Dinner with Andre. Steve Jobs (a stretch, but much more a play than a movie). There's some play adaptations which have few characters and mostly dialogue: Carnage, Who's Afraid of Virginia Woolf, Glengarry Glen Ross Linklater's "Before" trilogy is also heavily dialogue-based, but the there are multiple locations.