The Darkness is a game in which you get betrayed and extract revenge using demonic powers. You also eat hearts.
The graphics are nice and suitably dark, and New York has a grimy urban feel with tons of graffiti which always seems to be original, and most pieces of graffiti are used only once. The Otherworld sections ahve a suitably hellish look to them and the Otherworld soldiers all look twisted and demonic. All the characters look nice, and the npcs seem to almost always be different character models.
The storyline is very straightforward but can be confusing at times but is usually just a story of revenge, of Jackie getting back at the people who tried to kill him. During the story the entity known as The Darkness acts in a suitably creepy and morbid way through its dialogue. In fact the voice work of The Darkness is some of the best in any game, all the charcaters and npcs have scripts and respond when the player attempts to talk to them. The voice of The Darkness itself is excellent and really fits the role, with the tone changing from sympathetic or gleeful to angry or mocking.
The gameplay itself is very unique mostly because of the powers you will aquire. These powers are usually very useful and more than able to destroy your enemies easily. My favorite power is Demon Arm which bacically shoots out a spiked tentacle to impale anything infront of you. The gameplay also centers around the destruction of light sources with either guns or the Demon Arm, however about 2/5 of the way into the storyline you will be able to summon a darkling who is invulnerable to light and destroys light sources, making the task almost negligible. However he sometimes doesn't get rid of the lights you need him to or gets distracted by far off lights, he isn't much good in combat, and he dies fairly quickly if exposed to gunfire. Using darkness powers uses up your darkness energy, the meter of which is cleverly positioned on the side of both of the heads of the manifestation of the darkness, which allows for a more realistic hud (or lack of) and, well, just plain looks cool. You recharge your darkness energy simply by either standing in a dark area, or EATING HUMAN HEARTS! But not only does eating the hearts of your foes recharge your darkness energy and look cool, it also serves to increase your darkness level, which in turn increases the amount of darkness energy you have.
Both the environments of New York and the Otherworld are fairly big and open ended, however there seems very little to do in an area unless you are supposed to be there on a mission. Unfortunatly once you finish the main storyline you can't go back and finish your sidequests. However one neat aspect of The Darkness is that unlike other games it saves what you have already done or collected for your next playthrough (which mean that for some achievments like One With the Darkness, which requires you to use your powers a ridiculous amount of times, you can get achievments or unlock content over several playthroughs instead of trying to do everything in one).
The weapons in this game are very powerful and the auto aim is very generous, not to mention that the gunplay of The Darkness is some of the most satisying of any first-person shooter. The handguns have a bit of variety to them but the other weapons are all the same and while the handguns come in multiple flavors, the smgs only come in two. The dual handguns are by far the most effective weapons simply for their accuracy, power, and the fact that if you run out of ammo in one you simply drop it.
The main storyline is fairly short but the sidequests will give you at least another few hours of playtime. The multiplayer is weak and laggy and feels like it had good potential but was never finished. One of the most frustrating aspects of the game is the fact that sometimes it can be confusing as to where you need to go or how to get there. For example, there was an area I had only been to once and only because the storyline took me there through a route which was sealed the moment I left it. The next time I had to go there it took me a long time before I realised there was another entrance into that region, d'oh!
Overall The Darkness is a very fun game with a good storyline and great voice work and visuals thats just plain fun to play. Any console shooter fan should get this superb and fun game, spearing opponents on my tendrils and then eating their hearts never gets old.