Mary Grant, a convent girl, goes to Monte Carlo, and because of her winnings becomes the center of attraction. Prince Angelo Della Robbia falls in love with Mary, and introduces her to his brother. Prince Angelo, whose bride turns out to be Mary's friend Marie Grant, who had run away from the convent with a married man, Mary moved by her schoolmate's pleas, keeps her secret. Idina Bland, however, enraged at Prince Angelo's marriage, exposes the scandal. In the absence of Prince Vanno, Marie falsely asserts that the story is not hers, but that of Mary Grant who, by her silence, seems to admit guilt. Mary leaves Monte Carlo, but an old friend, Molly Maxwell, arrives and exposes the truth. Prince Vanno goes in search of the innocent Mary, arriving in time to save his love from adventurers who are attempting to steal her wealth.