Duchess Elisabeth of Bavaria, Sissi, prepares to join her older sister in Upper Austria where she is due to announce her engagement.

Engagement to Franz changes Sisi's life forever and her already difficult family relationship endures further strain; as wedding preparations commence, Franz's attention gets pulled away by the rise of his adversary Napoleon III.

The consummation of the wedding smolders into a damp squib, but the Emperor shows his affection for Sisi by pretending to his mother, the strict Archduchess Sophie, that everything went smoothly.

An assassination attempt inside the imperial couples' closest circle; Franz's political warmongering leads to consequences; fed up with her antics, Countess Esterhazy places Sisi under house arrest during her pregnancy.

Barely recovered from the attack, Franz hurries back to his troops and thirsts for revenge, yet the war turns into an unmitigated disaster for Austria; alone at home and rebelling against the court, Sisi helps as a nurse in a field hospital.

Sisi and Franz travel back to Vienna after the death of their daughter; they meet Sisi's family, who have come to offer their support.