I highly recommend Romanzo Criminale, it was shown on Sky Arts in the Autumn, absolutely brilliant,
Its in Italian with english subtitles, its the semi true story of the rise to power of a criminal gang in Rome in the seventies and eighties, its brilliantly acted and looks really authentic, its not about the Mafia although they are mentioned, but other large criminal organisations like the Cammora in Naples and Ndrangheta are, both these are equally powerful as the Mafia but we never hear of them.
Sky screened the first series but I am gutted there are no plans to show the second. but I will have to buy the DVD