Etienne Saint Nolff, a specialized educator at the Child Welfare Services of Indre et Loire, is visited by Jesus one night in July. Jesus offers him a job as a consultant, and Etienne accepts the proposal.
Shortly afterward, Etienne finds himself entangled in the rape and murder of Sandrine, his colleague and secretary. Losing his sense of purpose in his profession, he decides to investigate with the help of Cerise, sent by Jesus and tasked with finding and bringing back a deserter.
The initial clues lead them to a Parisian real estate company, the Fraternitas Immobili re Veauregard (FIV). Very quickly, Etienne and Cerise are confronted with a series of murders. The executives and collaborators of the FIV are being eliminated either by professional hitmen hired by an Italian company or by the celestial deserter.
In Paris, Etienne contacts a former police colleague who has become a lawyer, Charles Horace Estienne, known as the CHE.
As they dig deeper, Etienne and Cerise become targets for the hitmen.
Andr a, Etienne's partner, is kidnapped by Jules Berry, the deserter, who wants to exchange her for the fortune he has amassed in Jesus's name and plans to keep for himself, right under his employer's nose.
Cerise realizes that she is being manipulated by Jesus, who is her brother and wants to recover his loot without their father, God, knowing about his earthly schemes. Jesus wants to enjoy his money on Earth.
Jesus, who had involved the mafia in the plot, strikes a new deal with them. He gets to keep his loot, while the mafia aims to erase all traces of their involvement in the fraud, linked to the Ambrosiano scandal, by eliminating all the players at the FIV.
The exchange of Andr a for the money is set to take place in the suburbs of Tours. The mafia is lying in wait. Everyone starts shooting at each other. The CHE and his friends protect Etienne. Berry escapes. Hitmen try to eliminate everyone. Etienne rescues Andr a.
Cerise convinces Jesus to end the affair in exchange for her silence and the opportunity for Jesus to resume his schemes without incurring their father's wrath. She secures a permanent mission on Earth and ensures that Etienne gets to keep the loot. Andr a leaves Etienne, who then moves to Paris and changes his profession.