Lambert, a recovering sex addict, tries to redeem himself by becoming a marriage counsellor. He stays abstinent for several months, but his alluring assistant's unbridled sexuality tests his resolve.
The head of a famous artist with a sordid past is found in the catacombs in Paris. In his studio, Commissaire Rousseau and the young profiler Mariella De Luca discover a second decapitated body, his wife's. The mystery deepens when another head is found a few days later.
