The show is set in an English Country village occupied by a Quaker sect of the most killjoy kind. The curtain rises to find the non-Quaker villagers in a great state of excitement that has been prompted by the arrival of a mysterious Frenchwoman. They speculate as to the reason for her visit, quizzing Mrs Lukyn, the landlady of the hotel where she is staying.
The Frenchwoman is, in fact, Princess Mathilde, who has run away from her Cheltenham finishing school to await the arrival of her lover, Captain Charteris. They intend to marry straight away, despite the fact that Mathilde is already being engaged to Prince Carlo, of whom more later. Impatient for Chateris to arrive, she sings the waltz song 'Oh, time, time'. Charteris then arrives with his best man, the American diplomat Tony Chute, and the Parisian dressmaker Madame Blum.
We now meet Prudence, the Quaker Girl of the title. She lives with her Puritanical Quaker uncle and aunt, and yet longs for a more exciting life - and, most particularly, someone to love. She sings her lament in the song 'A Quaker girl'. Coincidentally, Prudence then bumps into Tony Chute, the best man, and they immediately take a fancy to one another. Madame Blum then enters and, struck by Prudence's charmingly simple grey Quaker dress, tries to persuade her to come back with her to Paris. Before they can do that, however, that have to 'Tip-toe' off to witness the wedding of Charteris and Mathilde.
The marriage takes place, and the wedding party plan to return to Paris. Mathilde will have to disguise herself as an employee of Madame Blum, as her family has been forced into exile by Napoleon and she must not be discovered there. Prudence, persuaded to drink some champagne by Tony at the wedding breakfast, is subsequently disowned by her family, and decides to go to Paris with the others.
Act 2 takes place in Paris. Thanks to Prudence, Quaker dress has become the latest fashion, and she now has 2 men vying for her attentions - Prince Carlo (whom you may remember was engaged to Mathilde) and Duhamel, a government minister. Prince Carlo invites Prudence to a ball, planning to seduce her, with the biggest hit song of the show: 'Come to the ball'. However, she turns him down. Later, despite the Prince's best plans to keep them apart, Tony finally proposes to Prudence and she receives her first kiss.
Mathilde's presence in Paris is eventually discovered, and the police turn up to arrest her. The only way that Prudence can persuade Prince Carlo to allow his former fiancee to escape is for her to agree to go to his ball. Not knowing the reason for her change of heart, Tony departs in anger, believing that his new love is already being unfaithful.
Act 3 takes place at Prince Carlo's lavish ball. Prudence, evading the Prince's clutches, finds herself alone with her other suitor, Duhamel, the government minister. She shows him proof, in the form of love letters, that he hasn't been entirely faithful to her. Ashamed, he agrees to allow Mathilde to remain in Paris.
Tony now appears and finds Prudence singing of him. She tells him that the only reason she came to the ball was to save Mathilde, and he forgives her. They are re-united, and the show ends happily for everyone.