Don Pasquale, a wealthy old bachelor, is outraged when he hears his nephew Ernesto intends to marry the impoverished widow Norina. He determines to marry himself and disinherit Ernesto. Ernesto and Norina despair, but their friend Doctor Malatesta promises to help them and teach Pasquale a lesson. Malatesta persuades Norina to disguise herself as his sister, then presents her to Don Pasquale as a potential bride. Pasquale is so delighted with the young womans docile behaviour that he demands they marry at once.