There’s something inherently scary about bugs and creepy crawlers before you even apply them to horror. Rationally, they’re so much smaller than us, so we shouldn’t be afraid. But they can bite, sting, and carry disease. Some are venomous, and some swarm in large enough numbers to be dangerous. That doesn’t even touch on how just the sight of them triggers a visceral response; they make us squirm. Naturally, horror often exploits that fear.

Take Arachnophobia, for example. If you didn’t have a fear of spiders before, this horror-comedy makes full use of the eight-legged critters and gets under the skin of even the most fearless. And much like Arachnophobia, these other ten horror movies feature creepy crawlers that’ll have you reaching for the bug spray.

Creepshow

Bugs only feature in one of the five segments, but “They’re Creeping Up on You” packs in enough roach terror that it’s a relief that they’re contained to a fraction of the runtime. Upson Pratt is a ruthless businessman. His germaphobia has him living alone in a hermetically sealed apartment. Karma gets ugly when Pratt finds himself fighting off hordes of roaches. Dealing with one bug is plenty. But hundreds upon hundreds at once, all scurrying about and finding their way into every nook and crevice in your home? The imagery will induce a shudder or two. So too will the behind-the-scenes making of this segment, in which the real roaches proved impossible to corral.

Eight Legged Freaks

Arachnophobia proved that venomous, normal-sized spiders are terrifying. Throw toxic waste into the mix, creating gigantic killer arachnids, and the temptation to nuke the planet to eradicate all things arachnid becomes very tempting. Luckily, Eight Legged Freaks takes a comedic approach in this love letter to the atomic ’50s. Giant spiders become slightly less scary when they chirp at each other in a cute gremlin-like language. It’s a fun, campy feature, but that won’t make it any easier if you’re an arachnophobe.

Phenomena

Dario Argento may be the ruler supreme when it comes to grossing out viewers with maggots. Even in a film where bugs aren’t the villain. Jennifer Corvino (Jennifer Connelly) arrives at a Swiss boarding school in an area stricken with a series of grisly murders. Her unique gift to communicate with insects and her new friendship with entomologist John McGregor (Donald Pleasence) and his chimp proves key in solving the murders. With bugs coming to Jennifer’s aid throughout, they’re not so creepy crawly here. At least not until the climax, when Jennifer finds herself submerged in a maggot-infested pool. Nope. No, thank you.

Slugs

Slimy garden slugs become more than a nuisance thanks to Pieces’ director Juan Piquer Simón. Toxic waste renders them carnivorous critters with an insatiable appetite. What’s worse is that they multiply and congregate in mass numbers, making these slugs like oozy land piranhas. In other words, the deaths are gruesome and ultra-gory. It’s bad enough when they devour their victims whole, but the worst kills are reserved for those unlucky enough to eat their eggs unwittingly. Being consumed from the inside out is as revolting and unpleasant as it sounds.

Bug (1975)

“Kill it with fire!” tends to be a typical response to an infestation, but this roach feature co-written by William Castle and directed by Jeannot Szwarc (Jaws 2) reframes the phrase through the bugs’ perspective. As in, this particular mutant strain of cockroaches can set things on fire once an earthquake frees them. Nature would’ve sorted itself out – these roaches aren’t used to living on the surface – except a scientist decides to breed them with a modern roach. Whatever could go wrong? As horror has taught us countless times, everything could and does go catastrophically awry. Super-bred intelligent cockroaches for the win.

The Bay

This found footage movie sees a seaside down under siege from an unknown virulent threat. First comes a gnarly rash, then vomiting, then a violent, disturbing death. Eventually, researchers discover it’s a parasitic ocean isopod that’s mutated to an abnormally large size thanks to a nearby chicken farm’s chemicals getting dumped into the ocean. This isopod is most commonly known as the tongue-eating louse as it enters a fish through its gills, attaches itself to the tongue while cutting off circulation until the tongue falls off, then acts as the new tongue. It then steals all the nutrients until the fish dies. In The Bay, this isopod is now large cockroach sized and can affect humans by eating its way out of them.

Ticks

Creepy crawlers are, well, creepy all on their own. Throw in chemicals, toxic waste, or in this case, steroids, and you get pure nightmare fuel in the form of turbocharged creepy crawlers. Common blood-sucking ticks become abnormally large and aggressive thanks to getting mixed up in a drug dealer’s quest to make his marijuana plants larger with steroids. The teens enrolled in an inner-city wilderness project find themselves in the path of these massive ticks when they set up camp in their territory. It’s goopy, gory, and cringe-inducing. The highlight of the film is the violent climax that goes full-blown creature feature.

Starship Troopers

Set in the future, humanity’s quest to colonize new planets led them to the discovery of a hostile insect-like alien species. The Bugs don’t take lightly to the invasion, and a war erupts. In other words, the bugs aren’t exactly the bad guy here. That doesn’t make them any less deadly, and in some cases- like the intelligent brain-sucking Brain Bug- very unnerving. This big-budget spectacle puts its emphasis on the human characters and their roles in the war, but director Paul Verhoeven never skimps on showing just how gruesome war can be. Especially a war with monstrous sized bugs of all varieties.

Mimic

Guillermo del Toro’s sophomore feature was set in a Manhattan where cockroaches were the harbinger of a deadly disease that targeted children. Under the CDC’s orders, entomologist Dr. Susan Tyler (Mira Sorvino) creates a new hybrid species derived from termite and mantis DNA to eradicate the roaches and die off shortly after. Only they don’t die. Unbeknownst to anyone, Tyler’s Judas breed evolves into human-sized creatures with the ability to mimic their prey; humans. Mimic answers the question of just how lethal insects could be if they were large enough, and it’s rendered even more skin-crawling thanks to the grimy underground setting.

The Fly

The 1958 original doesn’t get enough attention for being a genuinely great sci-fi horror movie that showcases just how awful it would be to turn into a fly. David Cronenberg’s masterful remake, however, takes it to a whole new visceral level. The aspirations of scientist Seth Brundle (Jeff Goldblum) to fine-tune and present his teleportation devices turn to devastation when a housefly sneaks in, and its DNA merges with his own. His revolting transformation from human to Brundlefly delivers unparalleled body horror that will instill an instant aversion to flies. The coarse fly hairs and loss of teeth would be sufficient, but The Fly takes it a step further by having the viewer get up close and personal with the way flies eat; by regurgitating enzymes and saliva from their stomachs to dissolve food to a digestible liquid. Yikes.