Floradora girl Peggy Martin has found a life she could only dream about. She's in love - real love - with a handsome man about town (Gene Raymond) who adores her. They marry and upon returning from a honeymoon cruise, Peggy finds he's purchased a breathtaking mansion in the nicest part of town. But times and fortunes will change, both for Peggy and her beloved 56th Street home. Kay Francis, queen of triple-hankie weepies, portrays Peggy in a brisk, decades-spanning melodrama that links the big turns of her life to the fading glory of her home. Break out the tissues when Peggy sacrifices her happiness for that of a young woman (Margaret Lindsay) in debt to gamblers - a woman who will never know Peggy is her supposedly long-dead mother.

This melodrama chronicles three decades in the life of the New York located title house beginning at the turn of the century when a chorine falls in love with a wealthy young man. He loves her too and this inspires the lass to leave her sugar daddy, marry and move into the beautiful home that is located very close to Park Avenue. The pair are deliciously happy and even more so when a daughter is born. Unfortunately, unhappiness comes in the form of the jilted lover who returns and threatens to kill himself unless the former dancer comes back to him. Concerned, she visits his apartment to dissuade him from suicide. A struggle ensues with his gun and he dies leaving her to spend twenty years in jail for the alleged crime. Fortunately, her husband's belief in her innocence and his devotion never wavers. Unfortunately, he ends up killed on the front lines during WW I. It is 1925 when the hapless heroine is finally released from prison. She finds herself confused by the many dramatic changes that have turned refined New York into the wild Big Apple of the 1920s. She is also upset that her late husband's family refuses to let her see her grown daughter. They pay her a large sum to stay a stranger. On a subsequent ocean cruise she joins forces with a card sharp and becomes a wealthy con artist. They decide to work in a speakeasy on 56th Street. Surprise, it turns out to be her old home and in it is still the beautiful Florentine medallion that once symbolized the undying love between the woman and her husband. Still she opens the house for its disreputable business. One night her daughter, a compulsive gambler, who of course, doesn't recognize her own mother, shows up and loses a lot of money. She and the card sharp get in a terrible row and the young girl shoots him. Her mother then tries to take the rap but the speakeasy owner doesn't buy it and tells her he'll cover for her on the provision that she remain in the house forever. She accepts the dubious proposition and the story ends.