Take a look at this sneak peek trailer for The Stanley Parable, coming out on Steam for PC and Mac. The Stanley Parable is an experimental narrative-driven first person game. It is an exploration of choice, freedom, storytelling and reality, all examined through the lens of what it means to play a video game.
You will make a choice that does not matter
You will follow a story that has no end
You will play a game you cannot win
…it’s actually best if you don’t know anything about it before you play it
TSP does not actually require Half Life 2 on PC, only the Source SDK which should download automatically when you start the game. On Mac, HL2 is required.