Dissatisfied with the way her own life is playing out, New York-based Wally Winthrop (Abbie Cornish) becomes obsessed with the romance between American divorcee Wallis Simpson (Andrea Riseborough) and England's Edward VIII (James D'Arcy) when Sotheby's holds an auction of the royal couple's belongings. Wally is especially drawn to Wallis' side of the story, and as certain events transpire in her life, the line between fantasy and reality begins to blur.