Sebastien relates the life of Marie Antoinette as she goes from being a teenager devoted to him, her pug dog, to becoming the Queen of France and mother to two children.
Pursuing a friendship and then a passionate romance with the young Marie Antoinette, dashing Swedish nobleman Count Axel von Fersen becomes a devoted companion to the entire royal family before attempting to help them escape in the wake of the French Revolution.
In 1769, thirteen-year-old Maria Antonia Josepha Johanna, daughter of Empress Maria Theresa, begins a journal chronicling her life at the Austrian court and her preparations for her future role as queen of France.