Prince of Darkness is one of John Carpenter's weirdest films. Released in 1987 (between two cult favourites: 1986's Big Trouble in Little China and 1988's They Live), it's overly high-concept and riddled with gaping plot holes. But damn, if it doesn't depict evil in one of the most repulsive and scary ways ever.
A priest (Donald Pleasence, aka Dr. Loomis from Halloween and one of several Carpenter regulars in the cast) discovers a secret that's been locked in a creepy church basement -- which is somehow filled with lit candelabras -- in downtown Los Angeles. It's a canister full of Satan, in the form of a swirling green liquid. The priest reaches out to a local college professor (Victor Wong, aka Egg Shen from Big Trouble), who assembles a crack team of students and scientists (including Dennis Dun, aka Wang from Big Trouble) for a slumber party of sorts, while they analyse the substance -- which, in addition to looking like an angry lava lamp, also has some very sinister powers. It's already extremely freaky, even before the thing starts leaking.
Carpenter's script (written under the name "Martin Quatermass," a homage to long-running British science fiction character Professor Bernard Quatermass) is a bit tangled.
The woo-woo stuff gets rather dense: Satan is the son of the Anti-God; Jesus was a member of a human-like alien race; mirrors can be used as portals between dimensions; a secret Catholic sect called "the Brotherhood of Sleep" has been covering up all this juicy info for centuries. It's best to just kind of go with it and not to ask too many questions along the way. (Same goes for the uneven acting which can be distracting at times.)
Otherwise, you'll rob yourself of enjoying the many wonderfully bizarre moments in Prince of Darkness -- including Alice Cooper (whose longtime manager, Shep Gordon, was one of the film's executive producers) as the leader of a group of blank-eyed homeless people who lurk 'round the church, waiting to attack any of the researchers who might try to flee.
And you'll also miss out on the most memorable aspect of the film: the actually terrifying way it depicts evil. Pleasence plays his man of the cloth as being gripped by white-hot fear from the start, but the other characters, being science-minded folks, take a minute to catch up. The eerie, obviously supernatural cues can't be ignored.
In addition to Cooper and company acting creepy on the footpath, there's tons of other creepiness.
Worms collect in writhing clumps on the windows. A corpse is reanimated by a swarm of beetles. The various pieces of scientific equipment begin to go haywire. Anyone who dozes off has a shared dream that seems to be a transmission of doom from the future (the year 1999!). A man rips his own throat out. And the theologist who's been tasked with translating the Brotherhood of Sleep's records keeps turning up ominous references to Satan and the End of Days.
It only gets worse once the Prince fully seeps out of his containment vessel and starts turning various members of the team into zombies. Gets way messier, too.
Extreme body horror, demonic possession, claustrophobia, mind control, apocalyptic unease, urban terrors, the realisation that everything you've believed about reality is false, the fear that the nice young woman you've just started seeing might sacrifice herself to save the world from evil -- Prince of Darkness holds nothing back. It may not be a perfect film, and that cliffhanger ending is an obvious tease. But it's highly effective nightmare fodder, with a bonus side of skin-crawling repulsion.