Sir Percy Blakeney (Leslie Howard) is an English aristocrat leading a double life, by day he's an effete aristocrat and by night he's the Scarlet Pimpernel, rescuing French nobles from the clutches of the French revolution under Robespierre's Reign of Terror. Not even his wife suspects that Blakeney is the Scarlet Pimpernel and his cause strikes close to home when his brother-in-law, a French nobleman, is taken by the French revolutionaries and sentenced to death by guillotine.