The daughter of Irish immigrants patches up differences between her father and grandfather and rises to the top on Broadway.

Irishman Michael Noonan does his best to avoid work of any kind, even though his beloved daughter Nellie tries her best to convince him to do some. When Nellie and her sweetheart, Jerry Kelly, marry over Michael's petty objections, he vows never to speak to Jerry, even though he reluctantly agrees to accompany the pair to America. After several years in New York, the three become citizens and Jerry becomes a policeman, but Michael still will not speak to him. When Nellie dies giving birth to a baby daughter, Michael again refuses to make peace with Jerry, even though he continues to live with him and take care of the baby. Many years later, Jerry has risen to the rank of police captain, and the baby, also named Nellie, has grown into a young woman who is the image of her mother, and like her mother is torn by her love for both Michael and Jerry. Their daily squabbling becomes more serious when Nellie takes an interest in young Dennis Fogarty, the son of Michael's old friend Timothy. Michael makes unreasonably objections against Dennis, while Jerry tries to make Nellie realize that Michael is using her devotion to him for selfish reasons. She continues to see Dennis, but is heartbroken when Michael leaves home after a fight over Dennis. Some time later, at the Policeman's Ball, Nellie and Dennis decide to take a walk in the park, and discover that Michael has finally gotten a job as a handsome cab driver. Despite his inability to control the horse, he seems to be suited for the job and all ends happily as the three generations are reconciled.