Getting lost in a good book takes on a twisted meaning here.
A reality is just what we tell each other it is.
Do you read Sutter Cane?
The third installment of John Carpenter's "Apocalypse Trilogy" (preceded by The Thing and Prince of Darkness), In the Mouth of Madness explores reality, fiction, and the thin, horrific line that separates the two.John Trent (Sam Neill), insurance fraud investigator, has just been placed in an insane asylum. Months earlier, he was hired to find bestselling horror writer Sutter Cane (Jürgen Prochnow). Cane has disappeared under mysterious circumstances, but his publishers think it might just be a stunt to drum up support for his next book, In the Mouth of Madness.When Trent finds that the covers of Cane's books seem to become a map to the supposedly fictional town of Hobb's End, he and Linda Styles (Julie Carmen), who works for the publisher, decide to go there and find Cane. What they find, however, is something much worse.
Apocalypse How: Humanity is in full-on societal breakdown, and may very well go extinct. It's left deliberately vague as to whether people are just losing their minds, or are being invaded by a species of Eldritch Abominations.
Author Avatar: The Sutter Cane that Trent encounters is strongly hinted to be only a representation of the real Sutter Cane, who is writing the story outside of the fictional universe that Trent and by extension the movie exist in. Either that or Cane's rewriting of reality has gotten so strong that he can visit his own stories at will.
Author Powers: Near the end of the film, Cane's powers have become so vast that the entire world is his story, and he doesn't even need to write about it anymore. If he thinks it, so shall it be, demonstrating it to Trent by turning the entire world blue just because it's his favourite colour.
Catapult Nightmare: Trent startles awake from his alleyway nightmare, but it turns out that he's still asleep when he finds the monstrous cop sitting next to him on his living room couch. He has a second Catapult Nightmare when he wakes up for real.
Clingy MacGuffin: Once Trent has the manuscript, he can't get rid of it. Even when he destroys it, it reappears very quickly.
To make matters worse, when Trent tries to explain to the publisher what happened and prevent the book from being published he finds out he already delivered it, the book's been published and is selling like hotcakes, and there's a movie due to come out in a month.
Confessional: Insane author Sutter Cane discusses the power of faith over reality with the protagonist while they sit on opposite sides of a confessional.
Cosmic Retcon: The film has some particularely mind-bending ones. The crux of the story is that horror writer Sutter Cane has become so powerful that his creations have become reality, and the protagonist John Trent finds himself in the fictional setting of his stories. By the time he gets back to the "real world" his partner Linda Styles has been written out by the writer (not even her boss, who sent them on their mission, can remember her), and Cane's reality-destroying novel was already delivered by Trent to the publishers and has been on the shelves for weeks, even though Trent just emerged from Hobb's End. The Cane that Trent encountered might also be an Author Avatar of the real Cane, who is writing the entire story of the movie (yes, the one you are watching), Cane might have been influenced by a monolith of Eldritch Abominations to change reality so they can transform it into something wholly alien, or Trent may be particularely insane.
Credits Gag: Right after the "No animal was harmed during the making of this film" blurb, they have a slightly different report on the humans.
Creepy Basement: Mrs. Pickman's basement. When Trent enters she has half mutated into some sort of monster, and kills her husband with an axe.
Downer Ending: The film ends with the apocalypse, as the entire world is attacked by Lovecraftian horrors and a large chunk of the population falls into insanity. Of course, if reality is relative anyway, then does this ending even matter/happen?
Dramatic Thunder: Thunder can be heard during Trent's stay in the mental asylum.
Driven to Suicide: One of the town's residents kills himself with a shotgun in front of Trent after his daughter attacked him and his wife. He makes it clear that he doesn't have a choice in the matter, as he knows that this is what he was created for in the first place.
"I have to, he [Suttter Cane] wrote me this way."
Eldritch Abomination: The Old Ones. When they enter reality through Sutter Cane's book, they herald the end of humankind.
Eldritch Location: Hobb's End for starters, but especially the interior of the church.
Endless Corridor: The passage way that leads back from Hobb's End to the real world.
Genre Savvy: Having read Cane's books, the characters know what to expect. Whether they choose to believe that the books correspond to reality is another matter.
A God Am I: Zig Zagged with Sutter Cane. In this case, he may very well be, as his writings have granted him the ability to recast the entirety of reality through his novels. On the other hand, it's made clear that he is actually in service to a host of Lovecraftion terrors that are slowly invading the world.
Go Mad from the Revelation: During the ending, after witnessing the collapse of human civilization in a rising tide of madness and mutation, John Trent cracks when he discovers that the nightmarish book that did the deed was just a novelisation of everything he did in the last few days. He finds this out by watching the film adaptation. More to the point, it's rather implied that Trent's burst of laughing madness is due to his realization that he is in fact a fictional character, perhaps even of not only Sutter Cane, but also the screenwriter of this movie.
Going in Circles: Trent tries to drive out of town repeatedly but ends up right where he he started.
Groin Attack: When he's being taken in at the mental asylum, Trent attacks one of the orderlies this way.
Insurance Fraud: A guy burns down his warehouse of fur coats, but it turns out just stashed them away, and gave one to his wife... and another to his mistress. Catching both those ladies in their coats gave the guy away.
Invincible Villain: The villain Sutter Cane is the author figure of the entire movie, and just makes any changes he wants to the story no matter how implausible or crushing to the protagonist's goals. Trent never stood a chance of defeating him; he's just words in Cane's imagination. The meanest part is that not even Only the Author Can Save Them Now applies here (except out-of-universe). Cane is both the villain and the author, and won't save Trent from ceasing to exist when the story ends.
Kick the Dog: Quite literally. Our introduction to the terrifying children of Hobb's End shows them running after a dog. The next time we see them, the dog has had one of its legs ripped off and is limping around forlornly.
Kill It with Fire: Doesn't work. Since at that point, burning the book is like trying to burn the entire world.
Maybe Magic, Maybe Mundane: Have Sutter Cane's books triggered a mass delusion that's causing more and more people to think they're being taken over by monstrous demons? Or are monstrous demons really taking over people who have read Sutter Cane? Characters who haven't read his latest book think the former, those who have read it think the latter, and at one point Linda says it won't really matter either way once the believers outnumber the skeptics.
Mind Screw: What's the difference between fiction and reality? According to this movie, nothing, up to and including the movie itself.
The Mistress: An Insurance Fraud scam is found out when a guy claims a warehouse full of fur coats was supposedly destroyed, but he kept the coats, giving some to his wife, who ratted on him when it turned out he gave some to his mistress.
No Fourth Wall: An in universe example that breaks through two fourth walls. At the end, Trent views the film you are watching, only disjointed and cut up.
Nothing Is Scarier: The Old Ones' arrival is heralded by a yawning void... of blackness. Linda reads out what the protagonist is seeing.
Noticing The Fourth Wall: At the end of his stay in Hobb's End, Trent meets with Sutter Cane. Cane reveals that Trent is in fact one of his characters. Trent refuses to accept this, exactly how Cane had written him.
Only Sane Man: John's insistence through almost the entire film. He gives up the pretense at the end. Although he really is the only sane man, because that's how Cane wrote him.Discussed by Cane: "Always looking for the con... even now you're trying to rationalize."
Phlegmings: Demonstrated by the Old Ones when they pursue Trent into the portal.
The Plague / The Virus: People beginning their slide into madness show plague-like symptoms of open sores and wonky eyes. At first it turns out Cane is behind it all, but then it's revealed that the Old Ones were directing everything Cane has done.
Police Brutality: As Trent walks through an alleyway at night, he catches a cop beating up a homeless man. He leaves it alone, but the cop is ready to dish out some more. He later sees a nightmare of the same scene, except that the cop has become an inhuman monster.
Red Right Hand: Readers of the books of hack horror writer Sutter Cane go insane and develop strange physical afflictions, like a second pupil in their iris, or bleeding from their eyes. And berserk homicidal tendencies, of course. Over the time, these minor affliction develop into serious bodily mutations- including tentacles, distended jaws, and reversible joints.
Rewriting Reality: Hobb's End and John Trent were written into existence by an author called Sutter Cane, who also produces a number of retcons that remove a character from existence and reshuffle an entire sequence of events within the film. By the end of the film, the entire world has apparently been absorbed by Cane's latest novel. It should be noted that once he finishes his novel close to the end of the film, Cane appears to be able to warp reality at will, as demonstrated with the conversations he has with John Trent.
Room Full of Crazy: Notably, Trent starts out the movie having made his own filled with drawn crosses with just a single black crayon. It's even lampshaded by Dr. Wren who thinks that Trent isn't as mad as people think.
"The crosses are a nice touch. They'd almost have to keep you in here after seeing these, wouldn't they?"
Rule of Scary: A rare in-universe example; Hobb's End runs on this because it's the product of Sutter Cane's imagination.
Lots to HP Lovecraft, including several names, like Mrs. Pickman. And the title is reminiscent of both Lovecraft's novella At the Mountains of Madness, and the town of Innsmouth, mentioned in several of his stories.
Spooky Painting: Mrs. Pickman's hotel lounge is adorned by a painting of a couple standing besides a lake. Every time Trent takes a look at it again, the couple transform more and more into shrieking human-tree hybrids.
Through the Eyes of Madness: The movie was heavily inspired by the Cosmic Horror of HP Lovecraft. To make it even better, the question isn't just limited to whether John Trent is (in)sane or not, but also whether he actually exists or is just a figment of the in-story horror writer's imagination (or for that matter, a figment of the screenwriter's mind). The man's not just in the mouth of madness, but being digested.
Title Drop: The movie title is that of Sutter Cane's latest novel. It's title dropped by Sutter Cane when he finishes the novel's manuscript for Trent to return it to the real world.
"All done. In the Mouth of Madness."
Also earlier by a newscaster:
"Police believe the riots began because the stores could not meet the demand for advance orders of Sutter Cane's latest novel, In the Mouth of Madness."
Torches and Pitchforks: Wielded by the corrupted inhabitants of Hobb's End as Trent is trying to leave with Styles.