At 33, Clément has spent his entire life in a monastery and is about to take his final vows to become a monk. He only knows the modern world through the books and correspondence courses he took at university. Orphaned, he was adopted by the manager of the monastery and taken under his wing by Brother Benoît. When the latter is found murdered, Clément will help Elli Taleb, a totally atheist police captain, to find the murderer. Guided by this singular inspector, who raises her three sisters alone, Clément will discover the world outside the monastery and the secrets of her past.