Fay Cheney (Crawford) is a rich widow. On a boat headed to England, she mistakenly enters the suite of Lord Kelton (Frank "Wizard of Oz" Morgan), an older English noble, who takes an immediate liking to the attractive young woman. Also on the boat is Lord Arthur Dilling (Montgomery), The Casanova, a young cad who starts aggressively pursuing lovely Fay.
What neither of them know is that Mrs. Cheney is actually a con artist and thief. She and her "servants" are all actually members of a gang, led by her "butler", Charles (Powell). Their whole objective is for Fay to worm her way into this particular set of rich folks so she can steal a priceless pearl necklace from the home of Arthur's aunt, the Duchess of Ebley. This is complicated, however, when Fay starts to fall in love with Arthur.
- Buxom Is Better: Lord Winton (Nigel Bruce), who is kind of gross, is telling a story about the girlfriend he had in India when he was young. He describes her as having "a nut-brown skin and the most beautiful figure", and he makes the hourglass gesture.
- Call-Back: Early in the movie Arthur wins an auction by distracting Lord Kelton with a fake phone call. Later he does this again to get Fay alone to ask her to marry him.
- The Con: Fay Cheney is a jewel thief posing as a rich widow. Her "servants" have all chipped in to fund her wealthy lifestyle long enough for her to worm her way into Lord Kelton's affections, with the ultimate goal of stealing the duchess's pearls.
- The Exit Is That Way: Lord Kelton, startled when Fay starts changing her clothes in his room, tries to exit and instead walks into the bathroom.
- Gilligan Cut: The other guests are speculating how Lord Kelton's meeting with Fay is going. One lady thinks that Kelton is asking Fay to marry him, and she imagines an elaborate proposal: "My dear Mrs. Cheney, I am the victim of the emotion of love. I offer you my undying affection, and my heart, and my hand." The film then cuts to Kelton telling Fay, "You must understand, we couldn't possibly have a low tariff and compete with coolie labor." He is at least self-aware enough to follow this up by asking, "Do you find me dull?"
- Internal Reveal: At the end of the first act it's revealed that Fay is a con artist seeking to pull off a heist. Her gullible rich targets don't find that out until the climax.
- Intro Dump: Arthur goes to ask a steward about Fay and gets a startlingly thorough briefing. Surprised, he says "What do you know about me?", and the steward then introduces him to the audience as well.
- Love Triangle: A single kiss reveals that Fay and Charles are an item, but by this time she's already in love with Arthur.
- Meet Cute: Fay meets Lord Kelton, and through him Arthur, when she goes into Lord Kelton's room by mistake. Later revealed to be an engineered Meet Cute to worm her way into Lord Kelton's inner circle.
- Parlor Games: The rich folk play a game called "Truth" that is basically a variant on Truth or Dare, in which you must answer a question honestly or perform some silly penalty like writing down the names of all your cousins 50 times each.
- Title Drop: Ends with Arthur kissing Fay and saying "that's the last of Mrs. Cheney." He kisses her again. She says "and that?" He replies "that's the first of Lady Dilling."