The story opens in an inland village in Ireland, where Jerry, the village blacksmith, toils, that he may wed Peggy O'Malley in a style befitting her beauty. Peggy's father, Michael, favors Jerry's suit, but Peggy has a mind of her own, and takes passage on a steamer bound for America. Landing in New York, she fortunately secures a position as a parlor maid in a wealthy home. Peggy attends a dance, where she falls into bad company. Two weeks later young Jerry reads in a New York paper, dropped by passing tourists, of Peggy's arrest for the theft of her mistress's diamond tiara. In another week he is by her side, and after a series of eliciting adventures, causes the arrest of the real thieves, recovers the diamond hair ornament, and secures his mavourneen's release. With tearful eyes and a joyous heart, Peggy marries young Jerry, and returns with him to the little cot in Ireland, where her sorrowing father is waiting hopefully for his runaway daughter.