In 1767, the British Princess Caroline is betrothed to the mad King Christian VII of Denmark, but her life with the erratic monarch in the oppressive country becomes an isolating misery. However, Christian soon gains a fast companion with the German Dr. Johann Struensee, a quietly idealistic man of the Enlightenment. As the only one who can influence the King, Struensee is able to begin sweeping enlightened reforms of Denmark through Christian even as Caroline falls for the doctor. However, their secret affair proves a tragic mistake that their conservative enemies use to their advantage in a conflict that threatens to claim more than just the lovers as their victims.