Pregnant and alone after the 1906 San Francisco earthquake, Jenny Sandolvar (Chatterton) tries her best to make ends meet for her son, Dan. But after being arrested for being part of a cover-up murder, Jenny gives Dan up to the prosperous Reynolds family to hide him from child services. However, she realizes he’s better off without her, so she lets him stay with the Reynolds for good.
Twenty years pass, and Jenny has watched Dan (Donald Cook) grow up into a prominent lawyer, who’s now running for district attorney. She has kept her distance all these years to protect him, but her business partner, Steve Dutton (Calhern), gets caught running bootleg alcohol under Dan’s new no-corruption policies, and Steve’s willing to expose the truth to Dan to avoid jail time. Jenny kills Steve, and in a strange twist of fate, Dan prosecutes her, sentencing her to death.
Frisco Jenny bears resemblance to another Chatterton vehicle called Madame X (1929), where a woman must give up her illegitimate son, and he ends up being her defense lawyer years later.
- Affectionate Pickpocket: The woman at the brothel is shown sitting on a drunken man's lap. While distracting him with a kiss, she steals his wallet from his breast pocket, takes the money out, puts the wallet back, then discreetly draws a little circle on his shoulder with a chalk (a sign to other pickpockets that he has no extra money to be fleeced).
- Dark Secret: The fact that Jenny is Dan’s mother. A secret that Jenny's willing to kill in order to conceal.
- Dark and Troubled Past: Jenny’s life: She loses her lover and father in the earthquake, gives up her son because he no longer knows his own mother, and continues a life a crime because it's the only thing she knows.
- Dating What Daddy Hates: Jenny is in love with Dan Sr. and is pregnant with his child. Her father won’t allow them to get married.
- Department of Child Disservices: Jenny decides to hide her Dan from Child Services because they want to take him because she’s a madam.
- Dramatic Irony: We all know that Dan is sending his own mother to the gallows.
- Downer Ending: Not only is Jenny going to be hanged for the murder of Steve, but her son will never know that she was his mother.
- Give Him a Normal Life: Once Jenny was rich enough, she went to the Oakland family that had kept her son for three years. But Dan doesn’t recognize his own mother, leaving Jenny devastated and realizing that his life would be better with the Reynolds family.
- Miss Kitty: Jenny is part of a brothel ring that brings in a lot of money.
- My Secret Pregnancy: Since this is the early 20th century, Jenny has to hide her pregnancy from the world.
- Sleazy Politician: Tom Ford, the former District Attorney. Jenny and Steve bribe him with a box of cigars and $10,000 inside the box for an added bonus.
- Steve tries the same with Dan, but it doesn’t work.
- Would Hit a Girl: When Jenny’s father finds out she’s pregnant, he slaps her across the face.
- Video Credits: Many Warner Bros. and First National films began this way in the pre-code era.
- Yellow Face: A very white Helen Eddy plays the Chinese Amah.