The Inner Shrine (1917)

Diane Winthrop, a wealthy young American girl, is the ward of Derek Pruyn, an explorer and a student. Derek is in love with Diane, but believes that he is too old to ask her to marry him. The Viscount D'Arcourt is visiting at a Maine summer resort where Diane is spending the summer at the home of Derek and his sister. The Viscount proposes and is accepted just as Derek has nerved himself to propose to Diane. A hasty marriage ceremony is performed and the Viscount and Diane go to live in Paris, where the Viscount proceeds to take up his former life of debauchery, and his wife, to get even with him, begins a flirtation with the Marquis de Bienville. The latter takes the flirtation seriously and when he finds out that Diane means nothing by it, he seriously compromises her. He and the Viscount have a duel, and the Viscount, at the end of his resources, instead of shooting at the Marquis, commits suicide. The Marquis flees to South America and aids in the rescue of Derek, who after Diane's wedding has gone to explore the upper Amazon. Diane returns to America and Derek brings the Marquis, his rescuer, home with him. The three meet, explanations are demanded, and Diane finally appreciates Derek's wonderful love for her and they are happy together.