An actress known for complexity embodies a similarly mysterious figure from the 20th century, who also had a need to perform. There are so many stories about Diana that it would be impossible to fit them into one movie—or even an entire series—so the filmmakers wisely focus on just one episode. It unfolds at a deliberate pace, with considerable attention given to sweeping and lovely visuals of a difficult situation. The key question surrounding this film is Kristen Stewart’s casting: how could an American actress portray someone navigating the world of the House of Stewart's descendants? She demonstrates the ability to do it convincingly, conveying a sense of barely contained emotion throughout. For the duration of the movie, she seems poised on the edge of breaking down, and it’s quite striking. Stewart’s portrayal of Diana is as noticeable as the way her clothing provides splashes of color against the otherwise muted backdrop. The supporting cast has limited roles, and conversations among the royal family are infrequent. The music is classical and understated, with jarring jazz underscoring the unsettling atmosphere within the country estate. The conflict between established customs and modern influences is central to the film—like a delicate bloom colliding with an armored vehicle. It illustrates Diana’s attempts to adapt to an institution steeped in centuries of tradition, highlighting how she doesn't quite fit in. The family seems perpetually expectant of her, even keeping her contained as if imprisoned behind fences, which she desperately wants to escape. Comparisons are made to Anne Boleyn—another woman who met a tragic end. The imagery associated with Diana’s home mirrors her past, something she has lost but longs to reclaim. There's a noticeable absence of affection within the royal family. Even the staff adhere strictly to tradition and protocol, with Spall acting as an enforcer of rules. The family and staff primarily spend their time criticizing or directing Diana, maintaining a constant distance—she’s often shown in isolation and relies on fantasy to cope. Ultimately, the film is very sympathetic toward Diana; the royal family doesn't appear much better than antagonists.

Source on TMDB