The Baronets of Ruddigore are cursed. Anyone who succeeds to the title has to commit a crime every day — or perish in inconceivable agony.

Robin Oakapple, a young farmer loves Rose Maybud, but both are too shy to tell the other. But Robin has a secret. He is really Sir Ruthven Murgatroyd, the rightful Baronet of Ruddigore, in disguise. His younger brother, Despard, believing Ruthven to be dead, has assumed the title. Robin's foster brother, Richard, seeking Rose for himself, tells Despard of Robin's deception, and Robin is forced to accept his true position, losing Rose to Richard in the process.