The ocean is scary. We know that. A gigantic body of water that takes up most of the globe, too deep for us to know the limits, where we can’t survive? A haven of creatures so huge and alien we’ve barely glimpsed some of them? All enough to keep me awake at night.
So it’s the perfect place to set a horror novel.
Here are a few of my favorite spooky books that use the ocean as a backdrop, whether the scares come from the water itself or use it as a metaphor.
*
Mira Grant, Into The Drowning Deep
Mermaids have come a long way from Ariel and her desire for legs. In Grant’s work, mermaids are creepy, bloodthirsty things, and footage from a mockumentary seems to show them killing an entire film crew. The public thinks the footage is fake, so of course, a group of scientists are recruited to travel back to the site of the slaughter and prove mermaids are real.
They prove it, all right.
Richard Chizmar, WH Chizmar, Widow’s Point
Technically, this is lighthouse horror more so than marine horror, but a lighthouse isn’t really scary without the broad expanse of the lonely ocean behind it.
Told in a found footage style, Widow’s Point follows a group of intrepid paranormal researchers spending some time in a legendarily haunted lighthouse. Obviously, they get way more than they bargained for, including violent ghosts, time loops, and a group of mannequins that refuse to stay still.
Hester Steel, The Faceless Thing We Adore
Another book that uses the ocean more as a backdrop, but also a very effective metaphor for the wibbly-wobbly timey-wimey shenanigans afoot. Aoife is adrift after escaping an abusive relationship, and is quickly taken in by a group (cult) that lives on a remote island. It seems like paradise, but a few things don’t really add up, and there’s a mind-blowing shift mid-narrative that took me completely by surprise.
This was one of my favorites of 2025.
Julia Armfield, Our Wives Under The Sea
If you like your horror light on the jump scares and gore, but heavy on the emotional devastation, this one is for you. Miri’s wife Leah returns from a deep-sea research mission, but something is undeniably off. Her skin doesn’t look right. The bathtub is her new favorite place to hang out. And it’s difficult for Miri to talk to her without the ocean somehow coming up.
This is a book about grief, at its center, and how letting go of someone is a process that can both begin before they’re really gone and continue for long, long after.
Gabino Iglesias, House of Bone and Rain
Set in Puerto Rico during a hurricane, House of Bone and Rain is a horror-noir revenge tale of five blood brothers who would do anything for each other. Including aiding and abetting a murder. While the ocean is a constant backdrop for the first part of the book, it shifts in to a starring role before the climax in an incredibly creative way.
It’s a heavy book, with themes of colonialism, poverty, and organized crime. But at the heart, it’s a story about how far you’re willing to go for your chosen family, and I loved the moments of wry humor amid all the bloody murders.
Cassandra Khaw, The Salt Grows Heavy
This one has the ocean more as a memory rather than on the page, but it haunts the protagonist completely enough that it never feels far away. A mermaid who was made Queen (you know this story) had daughters with teeth, and they’ve devoured the kingdom. The mermaid and her companion, the plague doctor, are now on the run from her bloodthirsty brood, when they stumble upon a strange encampment of children who are just as bloodthirsty.
I loved this completely twisted take on “The Little Mermaid,” which imagines them like something you’d see from a particularly scary National Geographic special.
Anbara Salam, The Salvage
Marta is a marine archeologist, and one of the few women in 1962 versed in salvage diving. So, amid the wreckage of her marriage, she’s called to Scotland to excavate the remains of a Victorian shipwreck left behind by one of the village’s heroes. Turns out, the hero wasn’t so heroic, and some dark spirit is dogging Marta’s steps. It could be the captain, or it could be a ghost from her own rocky past.
This is an excellent “haunting” book that made me peek around corners before entering dark rooms. Ghosts are scary enough, but a ghost in an underwater wreck? No thanks, but also, give me more.
Megan Bontrager, The Sea Hides Its Dead
Another book of the many on this list that have made me happy I didn’t pursue a career in academia. Caro tags along to look into a mysterious monolith that’s arisen off the coast that her mentor is convinced has something to do with the ancient Cult of Leviathan. He’s right, and it’s just as terrifying as it sounds.
This one combined my fear of the ocean with my fear of caves, added a dash of cosmic horror, and spun it into a claustrophobic labyrinth that I consumed in twenty-four hours.
***
