Actually the writer of A Prophet took over the show after the first season and i think he turned into a great show. I enjoyd it.

And yes some of the actors were connected to the Mob. There's even a scene in the show where the clan goes to a gambling club in Paris and take over the joint. One of the actors in the scene was actually involved in a similar situation in real life when he went with a bunch of Corsicans to the Cercle Wagram, the most prestigious gambling club in Paris, and took over the place. They showed up one morning and told the staff to leave because from now on the place was theirs. As I said, Corsican are fierce.

Another actor of the show ran another Gambling club in Paris. They all are connected to Jean-Luc Germani, one of the main Corsican Mob boss.