England, Christmas Eve 1991The British royal family prepares to spend the Christmas holidays at the Queen's Sandringham estate in rural Norfolk. Among the attendees is Diana Spencer, Princess of Wales (Kristen Stewart), whose marriage to Prince Charles (Jack Farthling) has become strained due to his affair with Camilla Parker Bowles. As the size-able staff of Sandringham, led by the capable Major Alistair Gregory (Timothy Spall), prepare for the royals' arrival, Diana drives around the Norfolk countryside in her convertible sports car. On the verge of a mental breakdown, she avoids heading to Sandringham until running into Royal Head Chef Darren McGrady (Sean Harris). She notes that the long-abandoned neighboring estate, Park House, used to be her childhood home. Then she notices a scarecrow in the distance and eagerly runs toward it with a nostalgic expression. Diana takes off its jacket, which once belonged to her father John Spencer, 8th Earl Spencer, and goes back to her car.When Diana arrives at Sandringham, her sons William (Jack Nielen) and Harry (Freddie Spry) are excited to see her, but she does not attempt to socialize with the royal family, who mostly ignore her. Diana's only real friend at the Estate is Royal Dresser Maggie (Sally Hawkins), who encourages her to both combat the royal family and fulfill the obligations expected of her. Diana finds a book on Anne Boleyn in her assigned bedroom. She begins to have dreams about Boleyn (including a hallucination of her at a Christmas Eve dinner where she imagines herself destroying a pearl necklace given to her by Charles and eating the pearls in her soup), eventually coming to believe that Boleyn's ghost is haunting her in her capacity as a fellow abandoned royal wife. Diana tries to visit her childhood home but is stopped by royal guards, who initially mistake her for an intruder.Christmas DayDiana attends the service at St. Mary Magdalene Church in Sandringham, where she notices Camilla among the gathered crowd and is photographed by numerous intrusive journalists. Afterwords, Diane holds a difficult conversation with Charles, who rebuffs her concern over William and Harry's participation in a pheasant shoot the next day and advises her to develop a stronger sense of separation between her public and private lives.Charles privately arranges for Maggie to be sent to London and spreads rumors that she had planted the Boleyn book in Diana's room and made critical comments about her mental health; McGrady denies that she had done so when Diana questions him. Major Gregory attempts to encourage Diana to conform to the pressures of royal life by reminding her that the soldiers of the British Army die attempting to protect the interests of the Crown (and by extension her interests); Diana responds by stating that she never asked anyone to die for her.After imagining wounding herself with a pair of wire-cutters given to her by McGrady, Diana avoids the formal Christmas Day dinner, instead running to her childhood home and gaining access to it with the wire-cutters. Memories of her happier girlhood overtake her, and she dances from room to room while imagining her younger selves. She considers committing suicide by throwing herself down a flight of stairs, but the hallucination of Boleyn stops her. Instead, she rips apart her pearl necklace.Boxing DayDiana wakes up in her room to find that Maggie has been called back from London. The two travel to a nearby beach, where Diana talks about her mental and marital problems. Maggie responds by confessing that she is in love with Diana, which she politely rebuffs Maggie's advances.After bidding Maggie farewell, Diana goes to the pheasant shoot, walks out in front of the crowd of hunters, and announces that she is taking William and Harry to London, to which Charles reluctantly agrees. Diana bids farewell to McGrady and Major Gregory returns the Boleyn book to the library. As they drive away, Diana and her children sing along to the song "All I Need Is a Miracle" by Mike & the Mechanics, passing the scarecrow again, now dressed in one of Diana's outfits. They drive to London, where they pick up some Kentucky Fried Chicken and eat it by the River Thames. In the final shot, Diana looks across the river, uncertain of her future but no longer feeling burdened by royal responsibility.