Don’t worry, they’re not just adapting blockbusters: this trippy Japanese walking simulator you can get for $4 on Steam has been made into a movie, too

Well, here’s a twist. Instead of making a movie based on a blockbuster game like Minecraft or Super Mario Bros, someone made one based on a $4 walking simulator you can finish in about 25 minutes. And just based on the trailer, it looks a lot more faithful to the source material than most game adaptations.

Both the film and the game it’s based on are called The Exit 8, and they both center around a sort of backrooms premise. In the game by Japanese developer Kotake Create, you walk down a Tokyo subway station corridor trying to find the exit. On your left are some framed posters, on your right a couple of doors, and overhead are fluorescent lights. Walk to the end of the corridor, make a couple of turns, and you find yourself back in that same corridor again.

But it’s not quite the same corridor, most of the time. Some detail of the corridor has changed: maybe one of the three doors is missing, maybe the exit sign is inverted, maybe the pattern on the tile looks different. Or maybe absolutely nothing has changed.

The rules posted on the wall of the tunnel are simple: if you notice a change (the game calls them anomalies), turn around and walk back the way you came. If you see no anomalies, continue forward. You have to choose correctly eight times in a row to reach the exit and escape the tunnel. Choose wrong, and you start over.

The Exit 8 is a neat mix of the backrooms and spot-the-difference, and it’s extremely unsettling: some of the anomalies are downright creepy, and by the way, you’re not alone down there in that tunnel. There’s a fellow with a briefcase walking through the same corridor in the opposite direction who completely ignores you—most of the time, at least.

It feels like a tricky game to make a movie about, but director Genki Kawamura has added some story elements, including the nameless main character getting a phone call with some life-changing news just before he finds himself stuck in this bizarre looping tunnel. We also see a child with him in a few of the shots from the trailer—in the game, you’re alone except for that stranger with the briefcase.

The hardest part of the game is when there are seemingly no anomalies and you start to invent some of your own. “Were the tiles different? Did that poster say that last time? Is something off about the lights?” As one Steam reviewer put it: “Pay four dollars to get gaslit for an hour.” (It’s a positive review.) I’m interested to see how much of that self-doubt the movie can emulate.

The Exit 8 (the film) is screening at Festival de Cannes this month and will be released in August. The Exit 8 (the game) is on Steam. I’ve included the game trailer below, so you can compare it to the movie’s trailer at the top of the page. They’re both pretty freaky.