Giulia, a Neapolitan girl, much against her will, becomes the mistress of a wealthy gangster. Her "protector" is stabbed to death by Giulia's hot-headed musician lover Tony (Francis McDonald), whereupon the heroine takes refuge in the villa of French playwright La Farge. Under La Farge's careful tutelage, Giulia develops into a famous actress, capturing the heart of the Duke De Chaumont. Though LaFarge himself has fallen in love with the girl, he does not stand in her way when she accepts the Duke's proposal. But Giulia has not reckoned with Tony, who is still crazy about her and still willing to kill any man who stands in his way. Tony murders LaFarge, then sets his sights on the Duke, intending to kill the poor fellow during the wedding ceremony. Hoping to save the Duke's life, Giulia pretends to have fallen out of love with him and returns to Tony.