Bernice is a young woman visiting her cousin Marjorie from her hometown of Eau Claire, Wisconsin. She possesses natural beauty, including dark hair and high color, but lacks the modern social graces expected in Marjorie's Jazz Age circle. Raised with traditional Midwestern values, she expects femininity to involve modesty and passivity. Her desire for social acceptance leads her to seek Marjorie's guidance to improve her popularity.

Marjorie is a popular young woman with a fairylike face and a dazzling conversational style. She embraces the shifting social trends of the Jazz Age, rejecting the older generation's moral supervision and expectations of female propriety. She confidently entertains multiple suitors and refuses to be tied down to any single commitment. She values entertainment and independence above sparing the feelings of others.

Warren is a nineteen-year-old student who casually attends Yale. He acts as a primary representative of the young men in Marjorie's social circle, evaluating the partygoers with a critical eye. Though he harbors a strong infatuation for Marjorie, he frequently shifts his attention based on social capital rather than deep personal loyalty.

Josephine serves as a matronly figure who struggles to comprehend the rapidly changing social dynamics of the youth around her. She adheres to older, more conservative standards of propriety and feels overwhelmed by modern situations. While she attempts to soften her daughter's harsh judgments, she ultimately avoids confronting or redirecting Marjorie's behavior.

Otis is a sixteen-year-old boy in Marjorie's social set. He exhibits the impulsivity and restlessness characteristic of his generation, freely mocking those who lack social grace while quickly shifting his loyalties toward anyone gaining popularity.

Charley is a young man described as lacking height, beauty, and social shrewdness. Because he does not possess the sharp critical eye of his peers, he is easily charmed by basic flattery and rehearsed teasing.

Draycott is a young man studying to enter the ministry. He aligns with the older generation's traditional Christian moralism and expresses strong opinions on the depravity of modern society, particularly regarding shifting standards in dress and behavior.

G. Reece Stoddard is one of the young men Bernice practices her conversational routines on. He represents the easily swayed male audience at the center of the local popularity contests.

Mrs. Deyo is a prominent local matron who upholds strict traditional values. She views modern youth fashions—especially bobbed hair—as severe moral failings and acts as a strict social enforcer.

Martha is a popular dancer who belongs to the rising "new money" class. Josephine Harvey considers her family common, but Marjorie defends her based entirely on her popularity with male dance partners.

Sarah is a young woman possessing the refinement of an "old money" European education. Marjorie dismisses her entirely because Sarah clings to traditionally moralistic views, rendering her socially irrelevant to the modern set.

Genevieve belongs to Marjorie's exclusive circle. She fully embraces modern fashions and attitudes, aligning herself with the popular crowd that dictates social success.

Roberta is a close friend of Marjorie who shares her modern sensibilities and sharp-edged conversational style. She happily participates in the group's efforts to challenge and pressure their peers.

Jim is a young man who has been privately engaged to Ethel Demorest for three years. He serves as a living example of the social policing in their community, trapped in an unfulfilling relationship simply because breaking the engagement would be unacceptable.

Ethel has been privately engaged to Jim for three years. She exhibits the same noticeable boredom as her fiancé, demonstrating the restrictive nature of traditional courtship expectations in their social circle.