It's quite a good piece of writing, though, there are some lengths on the description that hinders a little the picture of the main character's feeling. The relation between that prisoner, Dupont, and the Journalist intrigues well, I really liked that part where he "tames" that prisoner with a few sweet words.

DNA heredity of criminality is a touchy subject, beware of that :)

Nice writing, will be reading the suite!