Though the acting was bad (Italian TV actors may be REALLY bad, as they're often chosen because of their connections with politicos, not their skills), the directing was just average and there were several inconsistencies in the plot, this series must be rated high, because it's absolutely SCARY. I saw it when it was shown on the Italian state TV (RAI), and I remember it worked even on people who don't care for horror stories. The plot, its faults notwithstanding, is like a maelstrom: it takes you to bottomless abysses, and you can't do anything else, just be brought down and down and down.

The story focuses on a group of young people who get in touch with a sort of occultist sect which has been active since before W.W.II. Its chief is a dark character, whose name is Sinisgalli, who seems to have found a way to grant people immortality, but at a high cost. Sinisgalli is involved in some murders, and he also denounced Roman Jews to the Gestapo in 1944 in order to get their money. There are several plots which ultimately converge on a disquieting ending. The pace of the episodes is so well timed that they literally fly, leading you to a nightmare of terror and paranoia.

Highly recommended, though I doubt that there is an English version...