Ignore the synopsis on the main page written by somebody who hasn't seen the series. This rather odd BBC production is far more concerned with the sexual exploits of an alcoholic restauranteur than the ghostly goings-on its target audience probably tuned in to see. In many ways it resembles one of those movie adaptations of short stories in which the supernatural content can't be stretched to anything like two hours, so it gets rationed out in little dribs and drabs between huge wads of padding in which two people fall in love, or some other people debate the reality of improbable things the viewer already knows are definitely real even if the characters don't. Though since the series was based on a full-length novel by Kingsley Amis, presumably everything in it was already present in the source material.
Although the very first scene gives us a creepy, gory foretaste of the horrors to come, the remaining 150 minutes deliver extremely little of what we were promised before the opening credits of episode one, and much of what we do get is that scene repeated for the benefit of people who tuned in late. Instead, we get Albert Finney giving it all he's got as a sweaty middle-aged drunk we're supposed to believe is irresistibly attractive to women because the script says so. His extremely selfish and immature behaviour is camouflaged by making almost everybody else either a nonentity or a caricature. Some of the braying morons who frequent his jumped-up gastropub wouldn't be out of place dining at Fawlty Towers; his daughter-in-law, the one person who believes him, is such a new age cliché that every single thing she says or does is brain-dead neo-hippie twaddle; and the trendy vicar who tries to be a modern Christian by openly disbelieving practically all of his own religion would be perfectly at home debating theology with three Irish priests called Ted, Jack and Dougal.
If I'm making this sound like a comedy, that's because a lot of it essentially is one. In-jokes abound, from Finney seducing a woman by describing food in a (supposedly) sexy way, harking back to the most famous scene in his 1963 breakout movie "Tom Jones", to the casting of Nicky Henson in a fairly major rôle because he was in lots of sex and horror trash in the seventies. Frankly, it feels smug, and the genuinely scary moments juxtapose very awkwardly indeed with scenes of impossibly stupid and rather camp vicars casually telling their parishioners what a load of old tosh most of Christianity is, or an irrelevant and obnoxious character with the surname Burgess suddenly appearing for no reason other than to show the world what Kingsley Amis thought of another author with a notoriously vast ego.
The supernatural elements are (mostly) effectively handled, but there aren't enough of them, and the concept of a hero who may be seeing things because he's an alcoholic doesn't work very well when it's made as unambiguous as it is here that the weirdness is all literally true, except for one slightly silly genuine hallucination that happens far too late in the tale to make the viewer doubt the reality of everything else. As a traditional ghost story minus all the filler about our hero's amorous antics and so on, it's about the right length for one fifty-minute episode. Stretching it to three requires one hell of a lot of stuffing. And by the way, if you think deus ex machina plot devices are cheating, this story involves such an outrageously literal example that it has to be yet another of the author's little jokes! In the end, the whole thing stands or falls on whether you believe in and/or like the main character, which has a great deal to do with how brilliant an actor you think Albert Finney is. My answer to all of the above is "not really", so it didn't work for me.