Sir Percy Blakeney maintains a dual identity as a vacuous aristocrat in London and a daring rescuer of French nobility during the Reign of Terror. Driven by a commitment to save innocent lives from the guillotine, Percy operates under the alias of the Scarlet Pimpernel, utilizing elaborate disguises and tactical ingenuity to outwit the French revolutionary agent Chauvelin. The narrative follows the tension between Percy and his wife, Marguerite, whose own past and unwitting actions threaten to expose his secret identity. The story unfolds through a third-person perspective that emphasizes the contrast between the superficiality of high society and the high-stakes danger of clandestine operations.

Readers frequently highlight the novel as a foundational text for the modern superhero archetype, noting how the protagonist's dual life set a standard for future adventure fiction. Discussion often centers on the effectiveness of the pacing, which maintains tension through clever plot twists and the constant threat of discovery. Critics observe that while the prose reflects the stylistic conventions of the early twentieth century, the character dynamics between Percy and Marguerite provide a necessary emotional anchor. The work is widely recognized for its influence on the swashbuckler genre, with many readers appreciating the balance between lighthearted social satire and the gravity of the revolutionary setting.