The plot is actually a very interesting aspect of the game, but one that you discover as you progress through it. In an attempt to not give away anything on a game you may not have played yet, I'll gloss over it. Let's just say some very strange things happen. Combined with the overall dreary nature of the environments and the excellent sound effects, FEAR plays like a horror shooter. You never know when you're going to glance up and something freaky will be there waiting for you. I probably won't be saying too much when I mention that a little girl features prominently. In fact, different portions of the game evoke memories of Carrie, the Exorcist, and even Akira.
The best thing about the game are the gun battles. Gun fights are very visceral experiences, with bullets blowing things off shelves and holes in walls. The particle effects are great, from the tracer rounds to the explosions of cement as the walls take a pounding. Most of the weapons you use are pretty inaccurate as well, which just makes the whole experience even more exciting, especially when you get a lucky headshot in. There's nothing quite like some masked clone screaming as you blow his arm off. The addition of a bullet-time effect, slowing down time so you can watch individual bullets fly around, only adds to this. But be aware, all of these graphical niceties can be taxing.