Dutilleul makes no change to his rather inactive life, however, and a year later still retains his ability to pass through walls, although with no inclination to use it.
Each time, he signs a pseudonym "The Lone Wolf" in red chalk at the crime scene, and his criminal exploits soon become the talk of the town.
In order to claim the prestige and celebrity status "The Lone Wolf" has gained, Dutilleul allows himself to be caught in the act.
His headache goes away, but later that night, as he is leaving his lover's house, he notices a feeling of resistance as he is passing through the walls.
The medicine suddenly takes effect, and Dutilleul ends up trapped in the wall, where he remains to this day.