The Brotherhood convinces Joseph to help them infiltrate the prison. Ophélie coerces Father Maxence into divulging details on the man in Élise's locket.

With his newfound abilities as a blue-blood, Donatien tracks down Guy de Montargis, who makes a searing confession. Albert faces a tragic dilemma.

As the origin of the blue blood comes to light, Élise must form an alliance between nobles and rebels to avert its spread.

Joseph and Katell fall prey to Donatien's sinister scheme. Charles orders Pérouse to track down Élise and Lariboise.