The asylum is receiving a new inmate tonight: insurance investigator John Trent (Sam Neill). Although he struggles manfully with the guards, he cannot prevent himself being dragged to a padded cell and locked in, complaining loudly that he is not mad and that he is there under false pretences - or he does until the rest of the patients chime in and echo his sentiments. So if he cannot persuade anyone that he is not insane, what can he do? When Dr Wrenn (David Warner) goes to visit him, he finds that Trent's request for a crayon has resulted in both the cell and himself covered in crosses for protection... but against what?
In the Mouth of Madness was the third of what director John Carpenter referred to as his Apocalypse Trilogy which began with The Thing and continued with Prince of Darkness. That should give you some idea of where the plot ends up, but before you reached the finale there was some twisted fun to be had with the surreal and nightmarish twists of Michael De Luca's script. De Luca was soon to become a powerful production executive, but he did have a love of the fantasy genres and here his appreciation of the works of famed horror writer H.P. Lovecraft were married to the success of a Stephen King-alike popular scribe.
Trent tells Wrenn about how he has wound up in the compromised position he has, which means it's that old favourite, the flashback set up we have the story offered to us with here. Time was when Trent was just another cynical insurance man, until he was brought onto a new case concerning horror author Sutter Cane (Jurgen Prochnow) whose fame is such that he even outsells Stephen King in his field. But here's the problem: his publishers, led by Jackson Harglow (Charlton Heston), are eagerly awaiting a new book, which is being promoted as they speak, yet Cane has not delivered it yet. Worse than that, he seems to have disappeared off the face of the planet.
So it is that Trent is inexorably drawn into Cane's world, and when he teams up with publishing exec Linda Styles (Julie Carmen) to track down the place where he think he knows Cane is lying low, a road trip arises with both of them following Trent's lead, Styles more reluctantly than her new accomplice. As a portent of things to come, Trent has earlier nearly been axed to death by Cane's agent (Conrad Bergschneider) in a coffee shop - could the act of reading the new novel have sent him round the bend? If the answer to that offers no surprises, then at least Carpenter can amuse us with some reality warping plot developments.
With Styles driving, the two of them do find a way to Cane's hometown, named Hobb's End after a certain underground station in Nigel Kneale's classic Quatermass and the Pit, a favourite of the director's, but it appears to be deserted. It's not, as Styles spots a group of children racing about and there's a little old lady (who else but Frances Bay?) behind the reception counter of the local hotel, but despite Trent's scoffing at anything supernatural going on, his companion is not so sure. They do finally get to meet Cane, and if he's a rather cardboard menace (Prochnow doesn't get to do much more than purr and pose) the unspeakable evils from another dimension he is about to unleash are entertainingly presented. Though the film is too derivative to really rank among the best in the genre, it's a treat for all that, with Trent realising before the climax that he's a fictional character therefore damned not to be able to change anything. Not bad, then, and a bright spot for this director's patchy nineties output. Music by Carpenter and Jim Lang.
Skillful American writer-director of supense movies, often in the science fiction or horror genres. Comedy Dark Star and thriller Assault on Precinct 13 were low budget favourites, but mega-hit Halloween kick-started the slasher boom and Carpenter never looked back.