No, that's not just a screenshot of a black screen. That's Nyctohylophobia, a new free indie game by Sarper Sohelr, Onur Samli, Oguzhan Kukuil.
(Nyctohylophobia, apparently, is the fear of being in a dark forest at night. Better known as fear of slenderman.)
In the game, it's dark. And why wouldn't it be? It's nighttime, and you play a young person who has been sent by his/her tribe out into the night to hunt a beast as a rite of passage. It's pitch dark, and you have a single spear. The only way to find the beast is by using your ears, so it's best to play the game with headphones on.
It's a focused, interesting experience—not the most polished thing in the world, but another neat example of how focused game design can be interesting. (You'll need Unity Web Player to play the game in your browser.)
More games where you hunt using your ears, please! Pardon me, gonna go play some Far Cry 2.