Honore De Balzac's The Atheist's Mass is a work of fiction set in Paris which deals with the question of faith and atheism. It centers around the characters of the renowned French surgeon Desplein and his student Bianchon. Desplein is an atheist physician who has an extraordinary capability to diagnose diseases and specify their cures. His merit is recognized by his worst enemies. However, despite being an absolute nonbeliever, Desplein is always helping the poor and healing the needy for free. Bianchon, who soon becomes his only companion and best friend, discovers one day that Desplein attends Catholic masses at the church of Saint-Sulpice. He is simply astonished when he secretly sees him kneeling at the altar and making contributions to the church. Bianchon eventually decides to confront him with his mysterious behavior and Desplein reveals the secret details of his life story. The readers learn that, as a student, Desplein used to live in very miserable conditions in one of the dirtiest slums in Paris and was evicted for not being able to pay the rent. He was only helped by a poor water carrier named Bourgeat to finish his studies. The latter decided to give him the little money he saved instead of buying a horse and a barrel for his own job. It was only with the help of his poor friend that Desplein was able to become the great doctor that he is. Being a deeply devout Catholic, Bourgeat's altruism has greatly affected atheist Desplein who, after Bourgeat's death, decides to observe the Catholic mass for his friend's sake.