While CGI has lent a hand in the creation of some of the biggest blockbusters of all time, they occasionally hinder horror movies, and have made them much worse than they could be with practical effects or more classical techniques.
Horror movies are often most effective when they bank on simplicity, which can be seen through the success of found footage horror such as Paranormal Activity, which was made for a meager budget of $15,000 and yet turned a massive profit, sweeping a $193.4 million gross at the US box office. In fact, many iconic horror movies, such as John Carpenter's Halloween and Tobe Hooper's The Texas Chain Saw Massacre were made for minimal budgets as well. Movies which employ a lot of CGI tend to have higher budgets due to the rising cost for these special effects, which are most certainly an art form, but the genre in the past has relied on practical effects and make-up to translate their scares to the big screen in favor of digital effects.
CGI isn't always the downfall of a good horror movie, however, there's a fine line. Often, action horror franchises such as Greg Nicotero and Tom Savini in the 1980s. This is more to establish a sleek appearance, get away with massive amounts of destruction - like a zombie apocalypse - rather than focused in on something like a slasher stalking a residential neighborhood on Halloween night.
Horror Movies Often Suffer From Bad CGI
Modern horror movies aren't the only ones that have struggled with too much CGI. Often, sci-fi horror movies, such as Event Horizon use CGI to allow the audience to travel to locations where they otherwise could not, such as space. However, massive sci-fi horror movies like Alien managed to make space work in their favor - and even created some grotesque creature violence - through the use of practical effects and more basic cinematography. Event Horizon ended up being an ambitious project that ultimately bit off more than it could chew and, while there are some slick sequences, much of the special effects work seemed unfinished.
Creature features like Lake Placid, Anaconda, and Deep Blue Sea also end up struggling when too much CGI takes away from their realism. As these movies are meant to be based on animals that exist in nature instead of fictional monsters, there needs to be some level of realism for them to be successful. Often, the more successful examples of these use real footage of sharks or avoid showing them more often than they put them front and center. There's a reason why so many B-grade SyFy movies like Sharknado are about man-eating creatures; they lean heavily into CGI and excess, making it part of their brand. However, movies that were supposed to be serious such as Deep Blue Sea end up being mocked in hindsight for clips where the CGI is painfully obvious. More recently, movies like The Shallows and Crawl have brought these movies back to basics where the CGI really focuses on realism in design and takes care to ensure the final product feels like the real thing.
Other times the CGI ends up being problematic for horror movies is when it morphs an actor into something comically unrecognizable as anything even remotely scary. Cases like A Nightmare On Elm Street tried to recreate the franchise's villain, Freddy Krueger, with a different actor and smartly used practical effects, but combined them with CGI in a way that didn't do the movie any favors. The Platinum Dunes horror movie also felt too sleek to capture the magic of Wes Craven's original. CGI can be an asset to movies, but horror proves time and again that the basics are often key to success.
