On Christmas 1877, Elisabeth of Austria (Sissi) celebrates her 40th birthday. As First Lady of Austria and wife of Emperor Franz Joseph I, she is not allowed to express herself and she must remain the beautiful young empress forever. To meet these expectations, she follows a strict regimen of fasting, exercise, hair styling, and daily waist measurements. Suffocated by these conventions, hungry for knowledge and life, Elisabeth rebels more and more against this image.