One Romantic Night (1930)

A princess engaged to a prince falls for her brother's tutor.

Director: Paul L. Stein
Cast: Lillian Gish, Rod La Rocque, Conrad Nagel, Marie Dressler, O.P. Heggie, Albert Conti, Edgar Norton, Billie Bennett, Philippe De Lacy, Byron Sage, Barbara Leonard, Russ Powell, Florence Wix

Because of political exigencies and his father's royal command, the fun-loving Prince Albert is persuaded to court the favor of Alexandra, daughter of the dowager Princess Beatrice. At her country home, Alexandra makes it clear to the prince that a forced marriage would be distasteful to her; and as a result, he tries to win her. Beatrice, piqued by her daughter's coolness, compels her to make a last effort to accept the prince by inviting Dr. Haller, an astronomer, to a ball planned in Albert's honor. Albert declares his love, believing Alexandra is in love with the astronomer, and realizing her love for the prince, she dismisses Haller. Albert announces he must wed a Princess Marie, but at Alexandra's suggestion he agrees to elope with her to South America

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