Horror movies are primed to deliver more visceral emotional responses in an audience than just about any other genre — comedies can make you laugh, dramas can make you cry, but only horror movies can make you do both while you also flinch, gasp, and scream. Of course, the monsters aren't the only things in horror movies that can prompt an involuntary reaction. Sometimes you end up screaming in recognition because you'll be sitting down to watch Friday the 13th when all of a sudden you'll recognize an actor making a truly bizarre cameo. If you've ever thought to yourself that Fabio looks like an angel, you're not alone. The filmmakers behind The Exorcist III thought so too, casting the long-haired eventual I Can't Believe It's Not Butter! spokesman as an angel. Another bizarre cameo in the film comes courtesy of NBA star Patrick Ewing, who appears as the Angel of Death. Both characters show up onscreen during a dream sequence that features an angel leading a big band, a train station that's also heaven, and dwarves carrying around a grandfather clock. The Exorcist III has plenty of other odd celebrity cameos, including Samuel Jackson, Larry King, John Thompson, and, perhaps most strangely, former Surgeon General C. Everett Koop. It seems like when you're making a second sequel to arguably the best horror movie ever made, you have to make it stranger if you can't make it any scarier. These days, Bill Murray's public demeanor is closer to his classic characters in Ghostbusters and Caddyshack than the persona of most A-list actors, which is why it was such a delight to see the legendary comedian appear in Zombieland playing a slightly exaggerated version of himself. While Zombieland is a horror comedy, Murray's cameo completely changes the tone of the movie from slightly scary to nearly pure comedy as the main foursome wander into Murray's seemingly abandoned mansion. The set design is pure Murray myth, with props from his former movies and ludicrous paintings of the man hanging throughout the house. Silence of the Lambs is one of the greatest horror movies ever made, and also one of the few to ever earn an Academy Award. Many factors led to that critical acclaim: the steady direction of Jonathan Demme, the nuanced performance of Jodie Foster, and, of course, the scenery-chewing, flesh-eating character of Hannibal Lecter, played by Anthony Hopkins. It's an incredibly engrossing movie, but if you're a mega-fan of crooning songwriter Chris Isaak, you might get pulled out of the movie when he shows up onscreen. The Backstreet Boys warned us all along that they'd be back, but we still didn't believe them. Or at least we didn't think that they'd be back (alright) in the closing minutes of This Is the End. In Seth Rogen and Evan Goldberg's horror comedy, most of the action takes place in James Franco's house as the real-life celebrities are menaced by supernatural beings and insane survivors of the rapture. Perhaps unsurprisingly, that rapture doesn't include a decent chunk of the Hollywood elite, leaving Jonah Hill, Seth Rogen, James Franco, Danny McBride, Craig Robinson, and Jay Baruchel to hole up and hide from demons. Sometimes it's not the actual presence of a celebrity in a horror movie that's surprising, but rather how they use that celebrity. Instead of getting wrapped up in the ambiance of the film, you end up scratching your head wondering what the purpose of such a bizarre cameo even was. A perfect example is Tim Burton's 1999 adaptation of Sleepy Hollow, which cast Christopher Walken as the Headless Horseman. Let's be specific here, however: Walken plays the Headless Horseman before he loses his head. In other words, he plays a Horseman. You almost certainly know Tommy Wiseau for his cult hit film The Room, in which he delivers a truly inimitable, bizarre performance. Wiseau has the kind of strange charisma where you're genuinely distracted when he appears onscreen, which was bad news for 2016's Cold Moon. Despite Wiseau's cameo and a story by the writer of Beetlejuice, Cold Moon is definitely not a comedy. In fact, it's deathly serious, which makes Wiseau's cameo even stranger. For actors who play characters in long-running television shows, it can be difficult to avoid being typecast. After all, if you've managed to please audiences as one type of character for over a decade, why should a casting director take a chance on you playing a different sort of character? It might make sense, but it also makes for some very strange moments when you see those actors pop up in horror movies just to be killed. A perfect example of that is Robb Wells' cameo in Hobo with a Shotgun. Technically, this is less of a cameo and more of a small role, but Jack Black's performance as an overly familiar weed dealer named Titus in I Still Know What You Did Last Summer is weird enough to merit inclusion. At the time of the film's release, Black hadn't yet reached the heights of fame he'd scale after his work in School of Rock and Kung Fu Panda, but he was still recognizable for his role in the Tenacious D television show and other small movie parts. The original Scream more or less reinvented the horror genre, pushing mainstream horror out of the cookie cutter slasher rut that it had been stuck in and giving audiences characters that had at least seen a horror movie before… even if that knowledge didn't keep them from falling prey to a killer. As with anything successful, Scream created its own franchise, which led to the well-received Scream 2, but was starting to peter out by Scream 3. Still the second sequel does offer one delightful surprise cameo: Carrie Fisher playing an annoyed studio secretary named Bianca who bears an uncanny resemblance to Carrie Fisher and came "this close" to getting cast as Princess Leia in Star Wars. Much like your college roommate and TV Tropes, Cabin in the Woods seems to be obsessed with cataloguing and referencing the formula of horror movies. Nearly every scene in the movie either directly references or obliquely nods to popular horror conventions or even specific horror movies. That extends all the way to the climax, in which Dana and Marty find out that they're all part of a grand ongoing sacrifice which requires certain archetypes to be ritualistically killed for the pleasure of elder gods. Marty needs to die since he's the "fool," while the "virgin" can survive without ruining the ceremony. It's a pretty clear nod to the Final Girl convention, a term coined by writer Carol Clover in her book Men, Women, and Chainsaws: Gender in the Modern Horror Film.