As other reviewers have noted, this is an unjustly neglected Depression-era film. Directed by Frank Borzage (two Oscars) and written by Jo Swerling (Leave Her to Heaven, The Westerner, Lifeboat, etc.), it is a tough-minded, well-structured and -realized move about denizens of a New York City shantytown. They're grifters, beggars, and women forced into prostitution, but they're a community of people both good and bad, with loyalties as complex as any group's.
Perhaps primary among this movie's many admirable qualities is the contrast between Spencer Tracy's character, Bill, and Loretta Young's Trina. He tough-talking, physically aggressive, and evidently fearless-- but Bill is not the character who gives this film its steely sense of survival. While he blusters, Trina actually hangs tough (if that term can be applied to a character so ladylike). Her devotion to him is obvious, and complete. When she becomes pregnant, she says she will raise it herself if he wants to leave. Such is the dignity of Loretta Young's performance (at age 20) as a very simple, even simple-minded character, that she seems neither weak or dependent, but rather a woman who recognizes happiness when she finds it, and love, and who has learned the hard way that it's worth holding on to because it doesn't come around often, and what's rare is precious.