In this comedy, a wealthy matron is terribly upset when she learns that her socialite son is planning to marry a blue collar girl. Upon hearing the dreadful news, the irate mother immediately cancels her vacation in Europe, disguises herself, and takes up residence in her cousin's boardinghouse. There she encounters a dashing, sophisticated thief and discovers that he is planning to rob her lovely home in Washington Square. She and her maid quickly return to the endangered home and find the house awash with people. Among them are her son and his fiance, the would-be thief, and many reporters and cops. Appalled at the thought of scandal, the quick-thinking mother immediately congratulates the young couple and introduces the crook as her "art broker." In this way, peace is restored and all are happy.