FPS, horror and a great story mixed up with great voice acting and cutscenes.
After finishing the game, reading through the credits, I had a sort of sad feeling, knowing I won't find another awesome game like this in a while. Best FPS game I've ever played, clearly, but you can't talk about this game without mentioning the story. I still don't know which parts of the game were actually meant to be true - and how awesome is that.
The story starts from Jackie, the main character, wanting to avenge the bad guys for the death of his girlfriend Jenny.. and well, I still don't know if she was actually still alive. Up to you to interpret the story then! The game is actually not too shabby gameplay-wise, but hey, I loved it. You power yourself up with Essence you get along your quest, in a RPG manner. The main point is that the Darkness gets in control of you and being in the light will harm you - a twist I've never encountered before in a game. Enemies are pretty similar to each other(powering up as you progress, of course) but I didn't see it as a downside. A few boss fights during the journey wasn't bad at all either.
I myself haven't found a way to get my hands on the first game in the series but hell, I'd still recommend this one, even if you've never even heard of the series before. I'm actually already waiting for The Darkness III or such - hope there will be something like that.
So, bottom line: get it already. I bought it just to check how it was, had no expectations or such - don't let that 7.0 score fool you. I've still gotta say it was one hell of a game. One more time: one hell of a game.