This is a visually impressive period film, though it does have some problems when it comes to accuracy and historical detail. Georgiana Cavendish, born Spencer, was an exceptionally interesting and charismatic figure in British society during the late 1700s. She married the 5th Duke of Devonshire, a very wealthy and powerful peer, which was considered a fortunate match for the time. However, they were fundamentally incompatible; the duke was taciturn and viewed marriage primarily as a way to secure a male heir. Georgiana refused to accept a purely ornamental role or simply bearing children. Feeling isolated, she ultimately agreed to her husband’s affair with Lady Foster, who moved into their home and had children with him—a humiliating arrangement that the Duchess supported in exchange for maintaining a friendship with Lady Foster, on whom she became emotionally reliant. Even now, it's open to debate whether the moral choices of both women were justifiable, as well as how much Lady Foster intentionally sought to supplant Georgiana, whom she seemed to simultaneously envy and befriend. Beyond that, we know that all three individuals involved in this unconventional relationship had other affairs and romantic entanglements outside of it. When Georgiana became pregnant by her young lover, Charles Gray, she was compelled to travel to France to give birth, maintaining a close but discreet connection with her illegitimate daughter for the rest of her life. Upon returning to London, Georgiana underwent a transformation; by accepting her marital situation, she began seeking various distractions and escapes to make her life more bearable. Her appearances at social gatherings made her a fashion icon, and her political support for the Whig Party influenced British politics during that era. The Duchess also developed a destructive gambling habit, possibly stemming from depression or even an eating disorder, which significantly contributed to her deteriorating health. She died young, burdened by debt, surrounded by admirers, and with some literary works published posthumously. That’s a brief overview of this captivating historical figure. The film, directed by Saul Dibb and starring Keira Knightley, takes a rather superficial approach to her life and occasionally deviates from established facts (be advised), even while offering visual delights. The production quality is high, with the costumes being particularly noteworthy—they are detailed and beautifully crafted, along with the sets which were selected from luxurious estates that effectively transport viewers to the period. The cinematography and filming techniques were also well-executed, as was the soundtrack composed by Rachel Portman, which makes excellent use of baroque music. My primary criticism lies with the editing; it lingers too long on unimportant details, resulting in an uneven rhythm. The passage of time wasn't handled effectively either: the characters don’t visibly age and little seems to change, so we lose a sense of how much time has passed. Regarding the performances, Keira Knightley deserves recognition for her work. She has experience with period films and appears to have developed an affinity for this type of dramatic role, making her performance feel natural and well-suited to the character. Her interactions with Ralph Fiennes are compelling; he is excellent in portraying the duke’s reserved, distant, and occasionally rude demeanor, presenting him as a disagreeable and morally questionable figure. Hayley Atwell also delivered a strong performance as Lady Foster, although she didn't fully capture the moral complexities and ambiguity that characterized the historical figure. Charlotte Rampling and Simon McBurney also had memorable supporting roles. Dominic Cooper did his best in the role of Charles Gray, but I felt he was too old for a character who was several years younger than the Duchess.

Source on TMDB