Kinue Amano is a content and hardworking saleswoman in the futon department of the Echizen Department Store, where she consistently ranks as the top seller. She is completely unconcerned with fashion, wearing plain, shapeless clothes and thick glasses. Her comfortable life is upended when she is suddenly transferred to the high-end women's clothing department on the third floor. This new section is a sleek, intimidating world of style, run by the legendary and demanding director, Miki Jinbo. Miki is a glamorous and exacting taskmaster who works fifteen-hour days and lives by a strict philosophy: wearing uninteresting clothes leads to an uninteresting life. She immediately dismisses Kinue's plain appearance and lack of fashion knowledge.

Kinue struggles to adapt to the cutthroat environment, which is a stark contrast to her old job. Her supportive but traditional boyfriend, Tatsuya Yamachi, a car salesman, fails to understand her new challenges. Kinue’s initial attempts to sell clothes are disastrous, as her inability to match customers with flattering items leads to returns and criticism. After being publicly humiliated by Miki, she decides to transform herself. With the reluctant help of her sharp-tongued but skilled co-worker, Ryo Sasaki, Kinue undergoes a complete makeover, discarding her old look for a chic wardrobe. This external change boosts her confidence, and she begins to learn the complex art of being a stylist and salesperson.

As Kinue becomes more dedicated to her career, she finds herself mentored by the quiet and talented buyer, Yusaku Tabuchi, who sees her potential. The narrative follows her growth from an awkward beginner to a capable saleswoman and junior buyer, taking on challenging projects like reviving a struggling shoe brand and creating a marketing campaign for young customers. However, her professional success creates a rift with Tatsuya, who feels neglected and pressures her to quit and marry him. Faced with a choice between her comfortable personal life and her newfound passion for work, Kinue chooses her career, ending their long relationship.

The series culminates with a major crisis as rival department stores poach staff and a key deal falls through. Miki Jinbo is forced to resign, and Yusaku leaves to pursue a dream in London. Kinue is devastated but rises to the occasion, taking on a leadership role to orchestrate the critical Christmas sales campaign. She successfully rallies the remaining team, proving that she has internalized Miki’s lessons about leadership, hard work, and the power of clothes to express one's true self. In the final scenes, a transformed and confident Kinue, now in a management position, encounters a new, plainly dressed employee transferred to her department, and she repeats the same challenging words once spoken to her, completing her evolution. The show consistently argues that one's outward presentation is not superficial, but an integral reflection of one's inner spirit and ambition.