Marion Nairn, a young widow, is spending the summer together with her young sister Lucy at Boulogne with Justice Proudfoot and his wife. The Duke of Hermanos, who is also passing his Summer at Boulogne, one day catches sight of Marion, and from that time on, he is her devoted admirer. He stands outside the window and admires for a few days, but finally he enters the house and declared his passion. Marion, ostensibly to get rid of him, tells him that she is married, whereupon he declares that her husband must die, and goes forth in search of him.

When the maid tells him that Justice Proudfoot is the master of the house, he naturally mistakes that elderly gentleman for Marion's husband and challenges him to a duel, which of course brings Lady Proudfoot under her husband's suspicion. One after anther, the men in the piece are mistaken by the impetuous foreigner of his adored one, and one after another, he tries to fight them all. In the end, Marion succumbs to his passion -- it seems the only way to kill it.