In 1793, the terror of the French Revolution is at its height, and the guillotines are busy. But a mysterious figure is staging daring rescues, and Citizen Chauvelin, the head of the Central Committee of Surveillance, is determined to discover his true identity, and uses a number of informants, including the popular actress Minette Roland.

The Pimpernel is called upon to track down Helene, the daughter of the Marquis de Rochambeau. However, Chauvelin is also looking for her, and so is Gabrielle Damiens, the head of the local revolutionary regime. Sooner or later, their paths are bound to cross.

The Dauphin is being held prisoner by the Republicans. When he is captured by a masked intruder, Robespierre orders Chauvelin to find the boy before news gets out.

The Pimpernel rescues yet another damsel in distress, but in order to save her parents she tries to betray him to the French. The Pimpernel loses his wife in childbirth.

The Scarlet Pimpernel attempts to rescue Antoine Picard, who discovered oxygen, and prevent the French from developing an advanced explosive device. The Scarlet Pimpernel joins forces with Picard's sister, Françoise, in order to save him from the guillotine.

The Pimpernel's true identity is threatened with exposure when a foppish young aristocrat is mistaken for Sir Percy.