"The film had no story to tell." -- Alfred Hitchcock
Beefing on Hitchcock
Betty's wealthy father disapproves of his daughter's boyfriend, claiming he is only after her inheritance. She rebels by asking the boyfriend to marry her, resulting in an argument between the couple. When he attempts to reconcile later at her party, her father arrives unexpected to announce that he has lost his fortune in the stock market. Betty sends her guests away and insists her boyfriend depart as well. He sulks away, leaving the father to assume he was right all along. Betty struggles to make ends meet and care for her father, and she takes up an unseemly job entertaining guests at a restaurant. There, a stranger who had run into her several times throughout the film offers his support, should she ever need help. Her boyfriend comes to the restaurant to try to reconcile yet again, but his disapproval of her new job brings her to provoke him even further. He leaves, returning later with her father, who informs her that he lied about the loss of their money. He had intended to teach her a lesson and prove his suspicions about her boyfriend. Betty leaves in a huff and contacts the stranger, who agrees to take her back to America. He locks her in his room, and the boyfriend comes to her rescue. When the man returns, he is with Betty's father who has had the stranger following his daughter the entire time. The father is no longer opposed to Betty's boyfriend, and the two are to be married at long last.
While The Farmer's Wife was undoubtedly a "romantic comedy" I would go only so far as to call this a "comedic romance." The core is a romance, with elements of comedy keeping it light.
That being said, the story itself is quite weak and could have very easily benefited from some form of actual intrigue or mystery. Not that there needed to be any murder or criminal element of suspense to drive the plot deeper. A romance can be a story unto it self quite often, but the audience knew all along that the father was wrong about the boyfriend. Maybe if that had been a bit more ambiguous, the story would have felt a bit less shallow.
There isn't much to the movie, and the director admitted as much in his interview with Francois Truffaut. It's not entirely a bad film though, and I never felt my time was wasted... but the word "flawed" comes to mind and mostly due to the complete lack of intrigue in the characters. This could be considered Hitchcock trying his hand at other genres and story types, while trying to find his true place in cinema history.