Watch your back — and fingers! — around these seven ocean predators. One look at their hidden teeth, and you’ll think they jumped straight out of a horror movie.

The underwater world is home to a mind-boggling array of uniquely adapted creatures, including some with highly specialized toothy adaptations that can look nightmarish to the human eye. In fact, the razor-toothed mouths of unusual marine animals have long been the inspiration for scary movies, from the blockbuster shark-attack thriller Jaws to campy frightfests like Leviathan.

But reality can be even stranger than any movie monster. Even common sea creatures that divers see all the time can have strange hidden teeth if you know where to look. Take the California purple sea urchin, for example. Divers give them wide berth to avoid inadvertently pricking themselves on the urchins’ spines, but flip them over and you can find inch-long teeth in a ring that look like they could snip off the end of your finger.

Another common denizen of the coral reef, the moray eel, is a real-life version of the eponymous creature from the Alien movies thanks to a second set of jaws that can lunge forward from the back of its throat.

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The moray’s secret weapon is called a pharyngeal jaw, and it’s used like a grasping hand to hold onto prey as the eel swallows its quarry whole.

Perhaps the most unexpected set of hidden teeth can be found in a creature most divers know as a gentle giant. Look down the throat of a leatherback sea turtle, and you’ll find a gruesome maw encrusted with quivering spines like the sarlacc that ate Boba Fett. These are not true teeth — they’re called esophageal papillae, and they’re made from keratin (the same thing human hair and horse hooves are made of).

Cold-water divers have likely come across another unusual set of chompers peering at them from the dark crevices of rocky reefs. The wolf fish gets its name from the crooked mess of fangs that protrude ever so slightly from its Muppet-like face, while the back of its mouth has broad molars, including a plate of teeth at the roof of the mouth. The Atlantic wolf fish is found in the chilly waters of New England, while the wolf eel — its close relative — lives in the Pacific Northwest. Fortunately, these fish are quite docile around divers, preferring to use their formidable mouth for crushing urchins and other shellfish.

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If you ever see a cookie-cutter shark swimming near one of your appendages, you’d be well-advised to get out of the water. These tiny sharks are less than 2 feet long, but they have no qualms about nipping bites of much larger animals, including whales. They accomplish this with a suction-cup-like mouth and bottom row of teeth that’s straight, like a long serrated knife. The little shark sucks its mouth onto the flat surface of another creature’s skin, then uses its tail to spin around in a circle until it slices off a perfect, cookie-shaped disk of flesh.

The freakish-looking lamprey uses a similar tactic to the cookie-cutter shark, but rather than a row of teeth, the lamprey has no jaw at all. Its mouth is one big suction cup, barbed on the inside with vicious teeth that it uses to bore into the flesh of other fish, either eating them down to the bones or simply sucking their blood, depending on the species (there’s also a third type of lamprey that doesn’t feed at all).

The hagfish might look somewhat like a lamprey — they’re both from the same primitive class of fish, agnatha — but the hagfish has creepy characteristics all its own. It lives in cold waters from the shallows to thousands of feet deep, where it feeds mainly on carrion.

Hagfish are often first on the scene at whale falls — whale carcasses that sink to the deep seafloor, creating a microenvironment that sustains life in the deep ocean for years. Hagfish have a tonguelike organ that extends from their mouth with raspy keratin plates on the end, which they use to pull chunks of flesh into their mouth.