In this second adaptation of Frederick Lonsdale's play a conscience-torn woman tries to steal pearls from a trusting lady for her loyal friend.
On a ship Lord Francis Kelton (Frank Morgan) finds Fay Cheyney (Joan Crawford) in his room. Playboy Lord Arthur Dilling (Robert Montgomery) bets Willis (Nigel Bruce) he can win her but soon pays off. In London Fay and her butler Charles (William Powell) hold a charity auction, and a Duchess (Jessie Ralph) invites Fay to a weekend party. Arthur talks to Charles and Fay but feels defeated. Fay's servants plan to split what will be stolen, while Charles blames himself for making Fay a thief.
The party guests play truth or forfeit on personal questions. The Duchess tells Fay that she likes her and trusts her. Francis tells Fay of his wealth. Fay sneaks into the Duchess's room but is confronted by the maid. Arthur asks Fay to marry him, but she says no. Charles and the anxious accomplices get a telegram from Fay. The Duchess opens her safe and shows Fay her pearls. Fay finds Charles in her room and is reluctant. Charles learns of her marriage proposals and tells her to take her chance; but Fay says she'll get the pearls. Arthur sees Charles in the garden and asks why he is there. Fay sees Arthur outside her window, and he notices someone climbed the ivy. Fay signals Charles with the light and goes to the Duchess's room. Arthur enters Fay's room and sees her return with the pearls. Arthur tells Fay that he recognized Charles, whom he previously let escape. Arthur locks the door. If Fay stays, he won't say anything. Fay says she won't do it and tells Arthur to leave. He refuses, and she rings the alarm. Francis and the Duchess question Arthur, and Fay gives the Duchess her pearls back. Willis calls Scotland Yard. Arthur tells Fay he'll get her out. Charles comes in and stays with Fay. On the phone Charles as Arthur tells Inspector Witherspoon to come in the morning.
Inspector Witherspoon arrives. At breakfast Francis pleads for Fay, but others laugh until Francis says he mentioned them all in his letter proposing marriage that may be made public. Willis learns that Cousin John (Ralph Forbes) is not the cousin of his wife, and others are embarrassed too. Francis suggests offering Fay passage to America for the letter. Fay says she and Charles want to go to jail. Francis offers 500 pounds, but Fay asks for 10,000. Francis writes a check, but Fay rips it up. Charles says good-bye to Fay, because honesty bores him. Charles gives Arthur his watch back, but Arthur lets him keep it. Charles goes with Witherspoon, keeping his bargain. Arthur asks Fay to go see the bishop and kisses her.
Fay believes that a woman can only become wealthy by marriage or stealing and converts to the less dangerous option even though her thieving partner is a fine friend, who sacrifices himself for her. The upper class is portrayed as more concerned about their reputations than about justice.