The big brains at Blumhouse take another dive into their big bin marked “Things That ARe Scarey” (red doors, black phones, nuns etc.) and dredge up this wet attempt at making a film about a scary swimming pool.

Night Swim is ostensibly a horror movie in which a family moves into a house with a Pool only to discover the pool is evil. It can also cure illnesses in return for a child sacrifice; an enticing bit of small print for the dad (Wyatt Russell) whose baseball career has been cut short by illness, although he is pushing 40 which seems a pretty good innings. Regardless, he jumps at the chance to trade his disappointing son (Gavin Warren) for a shot at being the world’s oldest professional athlete.

It sounds like something from Treehouse of Horror (one scene even recalls Bart of Darkness), but is so serious and drab that any hope of B movie fun goes out the window faster than you can say The Sh-inning. What could have been a chance for a timely water pollution allegory, a campy plouf-spoof or simply some spooky underwater visuals is literally just people saying, “There’s something bad in the pool!” and “There’s nothing wrong with the pool!” back and forth for 90 minutes.

Even for Blumhouse this is an empty shell of an idea, neglecting the most simple scares and basic beats. The son is supposedly struggling at school but the film never bothers to show any of that, nor does it care to explain why the pool hasn’t been bricked up after multiple child drownings. It wants us to question nothing and expect even less; why would we possibly need a reason to care about some millionaires and their malfunctioning mod cons, like the TV in Paranormal Activity, or the robot butler in Rocky IV?

Notable only for the inclusion of Oscar nominee Kerry Condon (The Banshees of Inisherin) and a cat named Cider, Night Swim proves less scary than most public pools. At least put a bee in there. Or Michael Barrymore.