A woman masquerades as her own niece to get back at a neglectful suitor.

In England, at the beginning of the Napoleonic Wars, the vivacious twenty-year-old Phoebe Throssel eagerly awaits the proposal of her longtime admirer, Dr. Valentine Brown. Consequently, when the gentlemanly Valentine says that he has enlisted in the British army because he has no "wife, mother, or sweetheart," Phoebe and her spinster sister Susan are crushed with disappointment. Ten years later, Phoebe and Susan, who are now teachers in the Misses Throssel School for Boys and Girls, have their drab, "old maid" existence on Quality Street disrupted by the return of Valentine's troops. As soon as Valentine arrives, he calls on Phoebe to invite her to the homecoming ball, but is shocked by her tired, lackluster appearance. Humiliated by his revulsion, Phoebe sheds her unflattering clothes, styles her hair in ringlets and dresses up in a stunning gown. To Phoebe's surprise, when Valentine shows up to take her to the ball, he fails to recognize her and is convinced that she is a guest in the house. Phoebe, taking advantage of Valentine's confusion, tells him that she is Livvy Throssel, Phoebe's "niece," and accepts his invitation to the ball. There, "Livvy" attracts a crowd of young male admirers, whom she teases coquettishly, much to Valentine's dismay. After the ball, Phoebe continues her flirtatious impersonation of Livvy and causes her snooping neighbors, spinsters Henrietta Turnbull and Mary and Fanny Willoughby, to grow increasingly suspicious of her. At a second homecoming ball, Valentine scolds "Livvy" and tells her that it is Phoebe, not she, whom he loves. Although eager to return Valentine's love, Phoebe is unable to "bury" her alter ego because her neighbors insist on seeing "Livvy" in the flesh. In the end, Valentine discovers Phoebe's ruse and, with the help of a disguise, officially sends the niece away before the spinsters can uncover the deception. After a heartfelt kiss, Valentine proposes to the faithful Phoebe.