In 18th century Denmark, Queen Caroline Matilda is unhappy in her marriage to King Christian VII, who suffers from mental illness. Her life takes a dramatic turn when she meets Johann Friedrich Struensee, a physician influenced by the Enlightenment, and they begin an affair. As their secret romance unfolds, Struensee uses his influence to promote liberal reforms, including the abolition of censorship and torture, but is eventually betrayed and executed. The film's conclusion reveals the truth about Caroline's life, written from her perspective in a letter to her children, ten years after the tragic events that changed Denmark forever.