Based on the best-selling novel of the same title by Fannie Hurst, it tells the story of a woman who spends her life as the secret mistress of a wealthy married man.

In early 1900s Cincinnati, young and beautiful Ray Schmidt works in her father's shop by day and stays out late drinking beer and dancing with various men by night, although her stepmother disapproves.

On the day of the concert, Ray is late arriving because her younger half-sister Freda is suicidal over her boyfriend, Hugo, leaving town.

[6] Several years later, Walter, now a rising young financier on Wall Street, runs into Ray who is single and working in New York City.

However, his work, family and social commitments sometimes keep him away for long periods of time, causing Ray to feel lonely and isolated.

After Walter takes an extended trip to Europe with his wife, leaving Ray alone with insufficient money to live on, she breaks up with him and accepts a proposal from Kurt, who has become a rich automobile manufacturer.

He finds her distraught over Walter's death and also learns that his father had been paying her only a very small amount per month, thus proving that she stayed in the relationship for love, not money.

[7] Back Street tells the story of Ray Schmidt in a direct fashion, reflecting the very simple perspective of a woman of her kind in the 1930s.

The cinematographer, Karl Freund, incorporated pictorial techniques, such as employment of a moving camera on set or changes in lighting, to make the message of the scene more apparent.