The story in Dark Sector is worth mentioning, but only because of its deficiency. While there are story aspects to the game, which starts off twenty years previous in a Prologue mission that gives you a chance to get the feel for the controls in a relatively tame setting, the elements of it are confusing and dont really make any sense. Repeatedly, events occur throughout the game and the gamer is not given any explanation as to why. While this is slightly jarring, it doesnt really offset the gameplay.
If youre playing Dark Sector, you should be playing it for the combat. The gameplay in this title is similar to Gears of War, but there are things about it that are very different. One is the inclusion of the glaive, a projectile weapon that you can use to decapitate, or remove the limbs from, enemies. One of the best features of this weapon is that as the weapon reaches the target, you are provided with a close-up, slow-motion view of the kill. You can also upgrade the weapon with 'Aftertouch', which allows you to control the glaive in the air after you throw it and slice through targets around corners.
The glaive is also used for a number of other purposes in the game, like opening boxes, picking up items, and unlocking doors. It is also essential to complete the puzzles in the game, which find you imbuing your glaive with certain elements as it flies through the air, in order to complete some task. These puzzles are frequent in the single-player game and obvious after the first one you complete, though there is the occasional puzzle that is difficult to accomplish.
Fighting the AI is a treat in Dark Sector, since they seem to realize the same tactical issues as you do. They take cover, try and get you out from cover or flank you, and pull off other skills that make them almost as fun to fight as it is to kill them with the glaive. There are also a number of boss battles, all of which are different, that require you to figure out the right way to kill the boss before they can be taken down. They are difficult, but not too much so, and will usually just take time of fighting the boss before you realize the trick.
There is also a solid multiplayer mode with two different styles of play. While these two different game types were an interesting change from the norm in shooters, it would have been nice to see the inclusion of styles that were more similar to ordinary shooters, along with the other modes.
All told, Dark Sector is a shooter that feels refined in its execution. It doesnt have a strong story, but if thats what you need to shoot a bunch of bad guys, then there are other games out there that will deliver it. This one brings the bad guys and the fun, if you dont care why youre fighting.