Just powered through the movie Il Capo Dei Capi... it was a 6 episode (hour and half each), made for TV movie in Italy that tells the story of Salvatore Toto Reina, who was the main boss of the Sicilian Mafia in the 80's and 90's. It was phenomenal, the acting was great and I was so happy to be able to find it on Youtube.
If you don't know the story, I highly suggest looking at Toto Reina's wikipedia page... it's far more gnarly than any polished American mob story you will ever hear. The mafia wars at that time killed over 1000 people in a 2 year span, including bombings, mass killings of judges, cops, families, kids, etc... A horrible time to be alive in that part of the Siciliy.
It climaxes with the murder of Judge Giovanni Falcone, probably the craziest mob hit you will ever read about (a skateboard involved!). An insane story all around, and this movie definitely didn't need to embellish anything. Quite possibly the best and most realistic mafia movie I've ever seen.