Clive Barker's cult horror series that launched one of the most recognized character's of the genre: Pinhead
Summoned by an ancient puzzle box, Pinhead and the Cenobytes; Demons to some, Angels to others, show a whole nother world of indistinguishable pains and pleasures never before known.
The first movie was made in 1987 and was Barker's directorial debut. 1988 marked the first of 7 sequels so far, the last 2 of which were both released this year after being shot back to back. However only the first two are a continuing story, with #6, Hellseeker, bringing back one of the main characters from the first movies.
3-5 and 7 & 8 seem to be all but hated by the serious fans while 1,2 and 6 are regarded as the best. All in all i think each one is worth watching at least once.
I think Doug Bradley (Pinhead) is the only actor that really returns through out all 8 movies.