A really very bad movie, with a very few good moments or qualities.
It starts off with pregnant Linda Blair, who runs down a hallways to flee what might be monsters or people with pitchforks, I'm not sure. She jumps through a window and wakes up, and we see she is very pregnant. The degree to which she is pregnant varies widely throughout the movie.
She and an annoying and possibly retarded little boy who I thought was her son travel to an abandoned hotel on an island. Italian horror directors find the most irritating little boys to put in their movies! On the island already are David Hasselhoff and his German-speaking virgin girlfriend (you know how Germans are said to love Hasselhoff...). He's taking photographs, and she's translating an esoteric German book about witches, I think.
Also traveling to the island are an older couple who have purchased it, and a real estate agent, and a woman I thought was their daughter. Evidently she was an architect, and Linda Blair and the boy are the older couple's children. I guess they all traveled to the island together, but it really seemed like Linda and the boy were apart from the rest of them (maybe they were filmed separately).
The hotel seems neat, certainly from the exteriors, but it isn't used to any great effect. An old woman in bad makeup and a black cloak keeps appearing to the boy and chants something in German sometimes, which he eventually records on his Sesame Street tape recorder.
People start getting killed, either in their dreams, or sucked into hell or something. Some of these gore scenes are OK, but not enough to recommend the movie. Though the copy I watched stated it is uncut on the box cover, the death of one character whose veins explode really seems to have been cut. Much of the scene is showing another character's reaction shots, since we're not seeing anything ourselves. The creepiest scene is one in which a man or demon with a really messy-looking wound of a mouth rapes someone. He looked particularly nasty. There's a laughably and painfully bad scene in which Linda Blair is possessed. I wish if a horror movie is going to cast her, they would do something original with her role, and let her leave Exorcist behind her (except for the yearly horror conventions).
In the weird, largely Italian, tradition of claiming to be a sequel to something it is unrelated to, this is also AKA La Casa 4 and Ghosthouse 2. That is, it is supposedly a sequel to Casa 3 - Ghosthouse, La (1988) - it's not (that's also a better movie than this one). La Casa 1 and two were The Evil Dead (1981) and Evil Dead II (1987) - again unrelated to Witchery and La Casa 3 (and much better than those). There's also a Casa 5, La (1990) AKA House 5, which seems to want to be a sequel to the fake La Casa series and the series House: House (1986) House II: The Second Story (1987), The Horror Show (1989) AKA House III, and House IV (1992). How's The Horror Show fit in there? It doesn't really, it claimed to be a sequel, thus requiring the real series entry to renumber itself to cause less (or more?) confusion. Oddly, The Horror Show is also AKA Horror House, and La Casa 5 is also AKA Horror House 2. Does your head hurt yet?