The Deep House (2021)

A compact (85 minutes) little horror film about Ben and Tina, a young couple who like to record their explorations of abandoned places. Tina seems interested in history, Ben wants their videos to go viral so they can make money. Pretty sure no one who tried to go viral has ever actually done it. Also, he likes to pull pranks on Tina to scare her while they're shooting the videos, because he's kind of an ass like that.

Ben learns of a perfectly preserved abandoned house off in a little corner of a lake in France. So he and Tina go scuba diving into it. Yes, this was a bad idea.

They quickly find that when the guy said "perfectly preserved", he meant it. All the possessions are still there. Including lots of police fliers for missing children pinned on the walls. Like mysterious Super 8 camera footage. Like two dead bodies dangling from chains in a basement that was blocked off behind a big crucified Jesus.

It's fairly predictable from that point. Tina wants to leave, Ben keeps promising they will, but keeps wanting to explore, 'just one more room.' The underwater drone keeps shorting out. Tina goes from thinking Ben is messing with her, to increasingly frantic as she figures out he isn't. Which is bad since, you know, they're underwater and have limited air supply. Then the exit is mysteriously bricked shut.

The air supply works as sort of a time bomb for them, but it's really secondary as a source of tension. The matter of whether they can even find a way out is more pressing, as is the limits on their mobility and visibility. 

That's where the underwater setting really shines. When Tina is being pursued, you know that on land, she would be running full-out sprint. Underwater, even in scuba gear, the best she can manage is awkwardly kicking and flailing through the water. The movie uses first-person perspective a lot, so those scenes feel like being in one of those nightmares where you're trying to run but you're stuck in slow-motion. Maybe it's just me that has those. Their lights can only illuminate so much, and combined with the face masks, their field of vision is very limited. Great for the jump scares when they're looking around frantically and the light is wobbling all over the place.

And the movie effectively kept me in suspense as to whether Tina was going to make it out alive. Ben was always fucked. The stupid guy who thinks it's funny to mess around with stuff like this never makes it out alive. As it should be.