After his mother dies, John Breen leaves his abusive stepfather on his river barge and proceeds to fulfill a boyhood dream, to work on a skyscraper under construction. He gets friendly with the boss, Gordon MacClellan, who learns that he is John's father, but keeps it secret. John loses interest in girlfriend Kathleen, falling for more worldly Paula, who is actually MacClellen's ex-lover, who soon he finds out. He decides to throw himself at her just to get her away from John. But John misunderstands and Maclellan must finally reveal his paternity in a desperate bid to save him and get him back with Kathleen.