No One Lives Forever I and II.

The two greatest games ever made. Yes, they are not recent, but they rely on style and gameplay. Perfect single player.

I recommend them, because I myself am totally not into shooters. I find them tedious, and often of uninteresting subject matter.
Except for these two. Humour, style, wit, 1960's atmosphere.

http://www.gamespot.com/pc/action/no...ihw/index.html