Priest André is devoted to his job, which he always does with gusto. Just like his secret passion. But what has happened to make him suddenly look so demoralised? By dealing with a penitent unlike any other, André Martial will eventually be guided towards a solution to his problem.

At the convent, nobody has ever seen Sister Esther smile, which explains the nickname she received! But Sister Austere is also known for her steadiness, and it is her who is chosen one day to go out and look for the young novice Mathilde, who just escaped from the convent. However, this little trip will turn out to be far from trivial for Esther, whose big secret will eventually be revealed.