The Delacroix code: At the Louvre Museum a Eugène Delacroix enthusiast is killed after having admired one of the artist's works. Simon is the sole witness, a teenager with a quite extraordinary memory. Without having seen the murderer's face, his hypermnesia might still enable an identification. The youngster's life is now in danger.

Florence's father finds his old friend dead and calls her. Florence and Captain Verlay investigate the murder and try to find the connection with Camille Claudel.