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->''"Do it, Russell! Make sacrifice! Look! Look into the red eye of your god!"''
-->-- '''Reverend Marsh'''

Russell Marsh, a gay professor of history in Seattle, returns to his hometown of [[TownWithADarkSecret Rivermouth]], Oregon after a long estrangement from his family to execute his late mother's estate. He becomes reacquainted with his childhood friend and lover Mike, and over the next few days becomes aware that his father's New Age cult, [[ReligionOfEvil The Esoteric Order of Dagon]], is planning to bring about TheEndOfTheWorldAsWeKnowIt.

It should be stated straight up that ''Cthulhu'' does not have Creator/HPLovecraft's most famous EldritchAbomination in it. ''Cthulhu'' is loosely based on ''Literature/TheShadowOverInnsmouth'' with elements of ''Literature/TheCallOfCthulhu'' thrown in, but overall it's best if you view this movie as one that simply draws on the Franchise/CthulhuMythos rather than an adaptation of the above stories.

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!!''Cthulhu'' contains examples of the following:

* TwentyMinutesIntoTheFuture: Radio reports speak of Eskimo terrorists attacking U.S. arctic bases, guerillas on the 'former U.S border', rapidly [[{{Foreshadowing}} rising sea levels]], and the death of the last polar bear living in the wild.
* AbsurdlySpaciousSewer: The catacombs which "go on for miles" beneath Rivermouth. Filmed in the real-life [[http://en.wikipedia.org/wiki/Underground_Seattle Seattle Catacombs]] where one of the producers worked as a tour guide.
* BadassLongcoat: Worn by the cult leaders. We also see a line of candle-bearing figures InTheHood -- Russell is so freaked out he steals a boat to avoid them. [[spoiler:It's implied that these were the FishPeople.]]
* BearsAreBadNews: Inverted. We see polar bears swimming behind glass, and while it's not clear what they're supposed to represent in the movie, they do look beautiful.
** Probably has something to do with how a radio broadcast at the start of the film implies the [[ExtinctInTheFuture last polar bear in the wild died]] so only those in captivity remain. One could tie that to humanity's situation by the end of the film...
* BlackScreenOfDeath: The ending is a SmashCut to black so we don't know what Russell does.
* BlackSpeech: The Dagon cults' version of OminousLatinChanting.
-->"Ph'nglui mglw'nafh Cthulhu Rl'yeh wgah'nagl fhtagn!"
* BodyHorror: Averted, despite it being the main subject of "The Shadow Over Innsmouth". [[spoiler:Unless you count the FetusTerrible in the bathtub.]]
* CeilingCling: The FishPeople in the catacombs.
-->"There were ''things'', and they were everywhere! They were on the ground, they were on the ceiling, they were everywhere!"
* ChewingTheScenery: The drunken [[FatherNeptune old seaman]], Zadok.
-->"They ate children, DROWNING!"
* CreepyChild: The blind boy Kellin Miles, especially when he sits 'watching' the [[SnowyScreenOfDeath static-filled]] OminousTelevision.
* DarknessEqualsDeath: Russell wakes up in an alley to find that ''something'' is dragging him into the dark interior of a doorway. Not surprisingly he runs like hell.
* DeadManWriting: Russell is told his mother left a [[VideoWill message]] for him hidden in her house. [[spoiler:He instead finds it in plain sight on top of the TV/VCR. On the tape his mother starts to warn Russell that his life is in danger; she then hears a noise and quickly turns the camera off. The camera is then turned on again by Reverend Marsh, who implores his son to take his rightful place as leader of the Dagon cult. Russell is shocked to see his father has blood on his face and hands, implying that he murdered Russell's mother moments before.]]
* DoesntLikeGuns: When Mike suggests Russell take a pistol with him to investigate an AbandonedWarehouse [[DarknessEqualsDeath in the middle of the night]], he's annoyed that Mike even owns one.
* DoesThisRemindYouOfAnything: The movie is basically the classic tale of a gay man rejecting his close-minded small town and its lifestyle and values. It's just that in this case, those small-town values include [[spoiler: membership in an apocalyptic sea cult and churning out a few mutant kids.]]
* DoubleStandardRapeFemaleOnMale: Averted. [[spoiler:Due to his sexuality Russell turns down the offer of attractive [[TheVamp vamp]] Susan to impregnate her, only to be drugged and raped anyway. Russell first appears to have little reaction to this, but when he encounters Susan again he's noticeably angry.]]
* TheEndOfTheWorldAsWeKnowIt: Worldwide [[HatePlague rioting and madness]] occur in the leadup to the apocalypse, as foretold in ''Literature/TheCallOfCthulhu'' (''"with laws and morals thrown aside, and all men shouting and killing and revelling in joy"''). Best points go to the [=MP5=]-toting [[ActionMom soccer mum]].
* FloatingWater: The liquid wall [[spoiler:through which the Ancestor attacks Russell.]]
* ForeShadowing: Russell [[spoiler:shaves his head and starts wearing purple quite early in the movie.]]
* HeKnowsTooMuch: A deleted scene apparently has Zadok found floating, murdered by the cult for talking to Russell.
* HumanSacrifice: The cult of Dagon has apparently been sacrificing children (and other 'missing' persons) for some time. One horrifying dream sequence shows screaming children crammed into a wooden cage for the FishPeople to devour when the tide comes in. [[spoiler:At the end of the movie, Russell is called on to sacrifice his own lover.]]
* IfItsYouItsOK: Mike has an ex-wife and daughter, and regards his affair with Russell as simply an extension of their friendship.
* IfJesusThenAliens: Russell ridicules Mike's suggestion that the {{Absurdly Spacious Sewer}}s are the legendary [[http://en.wikipedia.org/wiki/Shanghai_tunnels Shanghai tunnels]] (subterranean passages allegedly used to transport men kidnapped as slaves) and says sarcastically, "What other explanation could there be, [=UFOs=]?" Which is amusing given the origins of the [[StarfishAliens Great Old Ones]].
* LittleDeadRidingHood: Julia (a blonde girl in a red top) the liquor store clerk who tries to warn the protagonist [[spoiler:and ends up [[ChainedToARock tied to a bitthead with barbed wire]] as a sacrifice to the Fish People.]]
* LovecraftCountry: Averted. The events take place in the [[UsefulNotes/TheOtherRainforest Pacific Northwest]], though according to the backstory the town founders originally came from New England.
* NightmareSequence: Several of these. In the first one Russell [[CatapultNightmare wakes up]] to discover the [[AllJustADream stone cudgel he saw in his dream]] is [[FantasyKeepsake lying on his chest]].
* NobleBigotWithABadge: The homophobic sheriff is determined to bring down the Marsh family, and beats Russell [[spoiler:for the murder of Kellin Miles. When Russell encounters the sheriff after his escape he thinks he's going to be shot out of hand, but the sheriff just tells Russell to go home because he's not after him...whereupon he's KilledMidSentence by Reverend Marsh.]]
* NoEnding: [[spoiler:As the FishPeople stagger out of the ocean and the world comes to an end, Reverend Marsh offers Russell the chance to appease the Old Ones by [[IfYoureSoEvilEatThisKitten sacrificing the man he most loves]] (Mike) thereby becoming the immortal leader of the cult. Although we see Russell raising the stone cudgel, the movie ends before revealing whether he kills his father or his lover.]]
* RainOfBlood: [[spoiler: Kellin Miles is murdered and his body tied up outside Mike's house. They only realise this when his blood starts to drip on them.]]
* RoomFullOfCrazy: The names of the missing (and soon-to-be-missing) are chalked on the walls and floor of the [[AbandonedWarehouse net shed]].
* SceneryPorn: The Pacific Northwest is certainly beautiful.
* ShoutOut:
** Apart from the Franchise/CthulhuMythos references, there are also homages to other movies like ''Film/{{Phantasm}}'', e.g. the Ancestor who was inspired by the [[Franchise/TheSlenderManMythos Tall Man]].
** The movie contains an estate auction that includes an item that might be the key to an ancient conspiracy. [[Creator/ThomasPynchon Its lot number is 49, of course.]] For an added bonus, [[spoiler:the end of the scene makes sense as an alternate ending for ''The Crying of Lot 49''.]]
* StalkerWithATestTube: Susan asks Russell to be a ChosenConceptionPartner; he's squicked out and refuses, only to get drugged and raped by Susan.
* StockQuotes: "[[Literature/TheSecondComing And what rough beast]]" is quoted by the sheriff who arrests Russell. He claims ''he's'' the rough beast. [[DoNotTauntCthulhu He's not]].
* StrangerInAFamiliarLand: Inverted. Russell is only returning to settle his mother's estate, and intends to leave as soon as possible. His family have other plans.
* TenSecondFlashlight. Russell uses his camera's flash to see in the pitch-black catacombs. It's no surprise that he runs into [[FishPeople something nasty]].
* ThrowingOffTheDisability: [[spoiler:Susan's husband claims to have lost the use of his legs and testicles in a construction accident, so it's OK for Russell to impregnate his wife. Later, after he's raped by Susan, Russell confronts her in an alley, only for her husband to walk up behind him and jab him with a knockout needle.]]
** [[spoiler: He's telling the truth about losing the ability to use his legs. He implies the Order will give them back to him if his wife births a child--which she did and they apparently lived up to their end of the bargain.]]
* TitleDrop: An obligatory one [[NonIndicativeName given that Cthulhu himself never shows up]]. Russell comes across Kellin Myles alone in a house, [[OminousTelevision staring at a TV set]].
-->'''Russell:''' Where are your parents?
-->'''Kellin:''' They live [[CreepyBasement downstairs]]. We're waiting.
-->'''Russell:''' What do you mean--what are you waiting for?
-->'''Kellin:''' Cthulhu. ''(ScareChord)''
* TorchesAndPitchforks: An angry crowd with burning torches shows up at the police station after Russell has been arrested [[spoiler:for raping and murdering Kellin Miles. He naturally thinks they've come to lynch him and desperately holds onto the door of his cell to keep it shut. In the morning he discovers the crowd (presumably Dagon cultists) have trashed the police station, unlocked the cell door and driven off the police so he can escape.]]
* TheUnreveal: [[spoiler:Russell and Susan's [[HybridMonster offspring]] in the bathtub. This is likely what pushes Russell over the edge. Also what happens to Mike.]]
* WhenTreesAttack: The tree-like creature glimpsed on a couple of occasions is presumably a Dark Young of Shub-Niggurath (The Black Goat of the Woods [[MotherOfAThousandYoung with a Thousand Young]]).

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