The Forest starts off simply enough: your character is in a plane crash, and when you wake you see what is presumably your son being carried away by a pale humanoid. After that, you're free to do whatever it takes to survive.
If you're lucky, or unlucky, enough to see some locals of the surrounding area, you'll realize that you're on an island populated by some kind human stripped down to their most basic instincts who have a penchant for cannibalism. No worries though, if you run away from them you'll most likely get away, and you can start collecting resources from the surrounding area to build a proper shelter.
But then you start finding effigies made up of body parts. And then you start finding pitch-black caves with huge amounts of corpses hanging from the ceiling. And then you start finding mutants that look like someone decided to make a spider out of fused human torsos.
The Forest is currently in development, but purchasing it now guarantees the full version when it is finally finished. The game is updated regularly with the new structures to build, animals to hunt, and enemies to evade.