I will spoil this movie. This is the warning. All the following is based on hazy recollection.
Terrifier was actually a breath of fresh air on the stale as fuck and lame woke horror genre (don't see Barbarian, Hereditary, etc) and a decent addition to the dead as hell immortal slasher genre. The sequel was not great but had some decent kills and added some fun stuff to the lore. Everything with Art and The Child was fried gold in Terrifier 2. It could have used some more perversion on his part, more nudity and transgression, etc. I was OK that Terrifier 2 set up a Final Girl, because I was hoping Terrifier 3 would kill her off in the beggining of the second act. That was what should have happened. Because the Final Girl trope was beaten to death by Scream and I Know What Jennifer Tits Hewitt Did Last Summer, along with dozens of others. Setting up who should have been the real hero of the movie, Jonathon Shaw.
Because in the era of the girlboss a beta soyboy learning to go sigma should be the new "Final Girl".
General plot of the movie: Open on random house with two parents and two kids being murdered (it's implied that the little girl is left alive but that's not Art's style and he does find her in her hiding place). They pussy out on the little boy being butchered on screen. Strangely they're all white and the standard nuclear family (not strange at all, there'd be hell to pay if this was in any way a non-traditional family). Art is doing it in a Santa suit. There is no context. Then we get a "Five Years Prior" placard.
Events at the end of Terrifier 2 - Art's headless body kills the first cop it runs into. It pulls the cop's head off and uses it to discreetly ride the subway. This entire exchange is fucking gold. Victoria, or we could just all her No Face from Terrifier 1, is in a mental hospital. Art's body shows up, kills a security guard played by Chris Jericho, and offscreen Art attaches his newly born head from No Face. This is when I started to realize that while this show has a ton of more money and 4-5 producers now, they're cheaping out on the grossness and weirdness instead of putting that new invested money on the screen for us to see. They're also attempting to court The Modern Audience as Art is no where near as despicable and perverse as he was in Terrifier 2, and he was a shade of his former self from Terrifier 1 in that movie.
Another subway ride, this one with newly re-headed Art and No Face. Another dude dressed as Art gets on the subway and remarks that Art and No Face's costumes look great. This is some meta bullshit, like Art and No Face are horror movie characters within the world of the horror movie itself? It's just a weird fucking way to get Art in a pristine costume again. I really enjoyed the laundromat scene from Terrifier 2, it was leagues better than this. I think regurgitating that scene would have been better than what we get here, because it brings forth more weird questions than it answers.
Art and No Face go hang out in an abandoned building for 5 years. It's so fucking lame that they actually have Art just sit in a fucking rocking chair and gather spider webs, like he wouldn't kill every spider that got near him. What ever happened to the significance of the Terrifier carnival ride? Why doesn't that come back? Wait for it.
Interesting creepy dinner scene where Final Girl is seeing her dead friend piss and moan about being dead. I would keep this too. Boring scenes of character development and NO interest being brought to the characters. Art gets a Santa suit, and kills a few cameos. Then he meets up with Final Girl at a mall to torment her with a santa mask on to hide his face. It's not set up how he got the mask, he just has one now. After giving her a little wave he subs in for a mall Santa that went on break, and nobody notices the evil gross clown wearing a red suit with blood all over it. He hands out presents to kids. All are unwrapped save one, which is given to a little boy. They finally notice and kick art out of the Santa area.
The little (yes he's white) boy opens the present and there's a hard cut to an explosion with ZERO human casualties. When I say that I mean they didn't use life-like dummies or even store mannequins painted flesh color. It's just a mall Santa display with a firebomb going off in the middle of it. The news later says there were something like 7 deaths and 8 critically wounded. The only person we know is dead is the little boy who opened it, the scene is shot to where you can't really see which kids are near him at the time of the explosion. This is the producers/director/etc pussying out again. The second time there's only been an implication that a girl was killed. Nobody classified "girl" is killed in this movie, merely implied to be killed.
Art shows up at a frat party where Jon Shaw is supposed to be but isn't. He kills his best friend and a slutty blonde girl who has a true crime podcast. They were set up as earlier in the movie. She has a nice rack. They set up a gratuitous shower sex scene with these two and Art interrupts with a chainsaw. They are both very nude and in flagrante delicto. They are both gratuitously chopped up with a chainsaw, but only simulated male nudity is shown (we get to see a male rubber doll get fucked with a chainsaw). The girl nonsensically covers herself up because when you're about to be murdered by a chainsaw it's the best time to worry about modesty. The cameraman helps out too. This series had female nudity back in Terrifier 1, and had the balls to show female nudity when it was becoming a faux pas to do so. Ever since 2 it's been avoided and made both of these sequels fundamentally tamer and lamer than the first movie.
Aside: Being transgressive in this day and age requires breaking the current rules of horror movies. Basically making a horror movie like it's 1984 instead of 2024. Some of current rules are:
1: There will always be a final girl, and she will end up virtually unscathed by the events of the film.
2: While there may be hot girls in the film, none of them will ever be nude or harmed in a sexually suggestive way.
Neither of these rules was broken by Terrifier 3. Both were broken by Terrifier 1, and for that reason it is and will probably forever remain the best and most gruesome in the series. End of aside.
So these two are killed.
During that time or perhaps before Final Girl is out of the picture for a minute and goes to get the sword from where she dropped it on the Terrifier carnival ride in Terrifier 2. This sequence does not appear in the film, it's merely mentioned before and after, and she has some dirt on her hands she has to wash off. The Terrifier ride does not appear in this movie. She comes back with the sword wrapped in a christmas present and hides it behind the tree. This is such a dumbass plot contrivance that even though it's set up, the payoff is complete weaksauce. The audience knows what's in the fucking box.
And for whatever reason Dad (yes I didn't introduce these characters because I didn't care about them) goes to pick up Jon at his dorm because for whatever reason he took a nappy poo and didn't make it to the frat party. When Dad arrives he calls Jon or receives a call by Jon but based on the countenance of speaking this was actually No Face, as we've seen per Terrifier 2 that Art's speaking accomplices can mimic voices. You notice this in the scene in question especially badly if you've seen Terrifier 2, but even a lay person would get an idea that there's something off about the call. What happens next is therefore not a surprise to anyone.
Final Girl comes home and goes to bed. Little Sis and Mom are downstairs. Final Girl is awakened in the middle of the night to talking downstairs. Going downstairs she hears what she thinks is Dad and Mom having a weird discussion about getting rid of Final Girl, but it's really No Face talking to herself and mimicing both voices. Art has nailed a decapitated and naked Dad to the wall, and put his head on top of the tree. An end table in the middle of the room has a head-shaped package on it. Mom is tied to a chair with duct tape. There's a tussle and Final Girl ends up tied to another chair. No Face unwraps the package, showing it to be a skull. She tells Mom it's Little Sis then Art and No Face do some seriously despicable shit to kill Mom. By far the best/worst kill in the movie. Then they bring Little Sis out of the other room where she was apparently just chilling and waiting for her queue (she is not in any way bound).
Then No Face tells Final Girl that the skull is Jon's. The script then dives off the deep end into an empty pool of contrivances and nonsense. Final Girl asks to open one of her presents. And No Face obliges, after Art breaks her hands then cuts her free. She opens the box, gets the sword, there's a fight, No Face dies and melts, Art gets pinned to a wall, then the fucking floor gives way to a hell dimension or some shit and Little Sis takes a header into the pit. Final girl pulls the sword from Art and runs over to help Little Sis. She hands Sis the hilt of the sword to hold then attempts to use the blade to pull Little Sis up like a fucking idiot. The sword does what swords do and cuts her hands up and she drops Little Sis. Art escapes. Final Girl is The Crow now, even without the sword she regenerates (which tangentially explains how she could fight Art and No Face by herself with broken hands)
The movie ends on Art getting on a bus and annoying another woman with his clown horn. He is still a scary looking clown covered in blood. And it's not Halloween. It's still Christmas time.
Ok, so how to you fix this using virtually the same resources? There are some unnecessary things in the movie. The included Angel crap from Terrifier 2 that doesn't actually matter in the current film. They wanted to go several directions but kinda failed at picking one and sticking with it. The Christmas theme is good, so drop the frat party. Don't bother explaining where Art was for 5 years, as any explanation given will be worse than leaving it vague and unanswered (cut the second subway ride with the Art impersonator and everything in the random abandoned house they hung out in).
The lovers could just be showering in the dorm itself on Christmas Eve which explains why nobody is around but the lovers and Jon (who is awoken by their blood curdling screams). Everybody else went home for the holidays. Obviously show the girl's knockers (maybe have Art cut one of them off for fun), and obviously spread the love when it comes to killing kids, not just white boys. Earn that hard R rating. Maybe even step up to NC-17 territory. Maybe they can't show kids being killed, work around that but don't discriminate and make it solely affect white boys.
Have Jon and Art share a scene after the lovers murder. Jon stumbles upon Art making a blood angel, grabs the discarded chainsaw and tries/fails to start it, then drops it and runs away from Art. Make it look like he got away, then give us the realization that he's the skull in that semi-final scene. Then Final Girl freaks out at the notion and Art hits her in the head/hands/knees with a hammer a several times and then No Face non-chalantly and unceremoniously slices her throat. As she's about to die Jon shows up to try to save her and Little Sis. Instead of the entirety of the dumb present subplot have him come out of nowhere with the sword (he went and got it, as Final Girl was too PTSD to go back to the Terrifier ride). He shows up, decapitates No Face, tussles with Art, pins him to the wall. No Face melts, but no hole opens. Art knocks back Jon, pulls the sword from his chest, then hurls it at Little Sis.
Jon goes semi-catatonic staring at Little Sis dying. The camera spins around Jon's head to show Art silently laughing his ass off behind him, does a full 360 view of the devastation in the room, and when it gets back to Jon's horrified face Art is simply gone.
The police show up and arrest Jon. Two slashed throats, a decapitation, and a stabbing in the house, a chopped up roommate and his girlfriend at the dorm. It's all pinned on Jon (his prints are all over the sword and the chainsaw, he's the only person at both locations at time of the murders, he's going to try to tell the jury an immortal killer clown did it. Open and shut case). The sword (and chainsaw) go into evidence.
Post-credits: The scene where Art gets on the bus and annoys a new person, BUT he's since washed his suit so he's pristine once again (implying that this is NOT immediately after the events of the film, but some time later). We basically have fully reset the plot of the series. There's no Mary Sue-perheroes, and all recurring characters are either dead or in jail other than Art.
Because this series is tumbling out of control and needs a good reset. This would have been a very simple way to achieve it. And, if it happens to be the last in the series, it would be a great bookend.