Honore de Balzac's 1828 novel, Les Chouans, is set against the historical backdrop of revolutionary France in 1799. At the time, a counter-revolutionary movement had taken shape in the region of Brittany, combining the forces of former aristocrats loyal to the House of Bourbon and a group of fierce guerrilla fighters known as the Chouans.

As the novel begins, the Chouans, seemingly led by the roguish Breton, March-a-Terre, but in reality led by the youthful Marquis de Montauran, ambush a detachment of Republican troops escorting a group of Breton conscripts under the command of Colonel Hulot. Although, after a bloody battle, the National Guard of Fougere comes to the rescue of the Republican troops, the Chouans' attack has been effective, allowing the potential conscripts to escape.

The French authorities begin to realize that conventional tactics will fail against a guerrilla army fighting on its own ground. So, for the sum of 300,000 francs, the Minister of Police, Joseph Fouche, engages Marie de Verneuil, a woman of great beauty and charm, to spy on Montauran while seducing him. Also dispatched with her is another government spy, Corentin.

Hulot is assigned to escort the coach of Mme. de Verneuil and her maid Francine across Brittany to Mayenne, with Corentin following at a distance. While stopping to dine at Alencon, they meet Madame Gua and her putative son, Monsieur du Gua St. Cyre. It's obvious to all that this woman is much too young to be the young man's mother, and there is speculation at the inn that he is, in fact, the Chouans leader, "The Gars," aka the Marquis de Montauran. March-a-Terre puts in an appearance, and is recognized by Mme. Gua as her former lover, Pierre.

As the journey continues, Mme. Gua and her alleged son now share the coach with Marie de Vernueil and Francine. It soon becomes clear to all that Marie and "The Gars" are falling in love. When they next speak privately, Marie accuses "The Gars" of being the leader of the Royalist troops, which as a Republican, she despises. He denies the charge, claiming a false identity.

The travelers reach the Chateau Vivetiere, upon which the Chouans have planned an attack. Captain Merle, charged with the security of Marie after the angry departure of Hulot, fears for her life when Mme. Gua accuses her of being a spy. Merle's adjutant, Gerard, advises Marie to leave immediately, but now consumed by her love for "The Gars," she refuses. By a series of serendipitous events, she manages to escape with her life when the Chouans attack.

There is an extended exchange of plots and counterplots by Republican and Royalist forces, as each side strives to gain the upper hand, with Marie de Vernueil terribly torn between them, due to her blind love for "The Gars." Finally, through the machinations of Corentin, who has been persistently trying to separate Marie from "The Gars" for the sake of the Republic, she is deceived into believing that he has cheated on her with Mme. Gua. With Marie as an accomplice, Corentin lures "The Gars" to a house to meet with her, unaware that it is surrounded by Republican troops led by Hulot. They realize that Corentin has deceived Marie about "The Gars"'s betrayal, and they decide to marry immediately. Marie warns her new husband about the troops surrounding the house, and he leaves in a disguise. However, despite Marie's efforts, when the Republican forces attack the house, both she and her new husband are killed.