Need a little time to think this over? That's understandable. The sale is running for 48 hours (well, 47 hours as of this writing), so you don't have to decide right now. But if you've been waiting for a chance to get into this modern horror and conspiracy game, $15 isn't a bad price to start in. And the game did just get a secret agent-themed update, if that floats your boat.
[Thanks to Zach for the tip!]