Usually the scariest part of adventuring on a Mac is the thought of simply finding a game to play. But thanks to Frictional Games, both Mac and Linux gamers can now get their chills in the playable demo of Penumbra: Black Plague.

The critically-acclaimed Penumbra games, soon to be joined by a final expansion called Requiem, are horror titles that rely heavily on real-world physics, allowing far more hands-on interaction with the environment than most adventures. Players assume the role of a man named Philip, who follows in the footsteps of his dead father and finds himself trapped in an underground tunnel complex in the frozen north of Greenland. Unfortunately for Philip, he's not alone, and the games also involve a certain degree of action-based elements in surviving the dangers, though far more in Penumbra: Overture than its sequel.

The demo is taken from the game's early levels, and can be found at the developer's website. The release of the full game is expected next week, along with an update to Overture.