Forbidden Paradise by Ernst Lubitsch

5.20

Alexei, a young officer, saves the Czarina of a small European kingdom from revolutionary conspirators and is rewarded with her love. Infatuated, he deserts his sweetheart, Anna, the Czarina's lady-in-waiting, only to discover that his Queen is far from true to him. Desperate, he joins the revolutionists and plots against her. The Czarina pleads that she loves only him, and he swears no harm will befall her. Meantime the chancellor nips the revolution in the bud, and the Czarina orders Alexei's arrest. But she causes herself such unhappiness in doing so that she releases him from prison, relinquishes him to Anna, and seeks solace in a new affair with the French Ambassador