Adrien Sixte is a reclusive intellectual known for his theories on psychological materialism. Sixte’s orderly, self-enclosed world is violently interrupted when a desperate mother petitions his help and a judge summons him to a criminal trial. The young defendant, Robert Greslou—a student and self-styled disciple of Sixte—has sent his master a confidential memoir written in jail. Greslou’s psychological self analysis traces the nexus of causes that propelled him to his current predicament. The memoir culminates with his experience as a tutor for an aristocratic family: when he experiments with the affection he inspires in a young girl, the disciple’s actions eventually leading to her death.