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.