It was supposed to be a routine mission three years ago. Enter a bunker deep inside Iraq-territory, retrieve a chemical weapon and get out. But inside the complex was no chemical weapon. Instead you encounter mutated humans and other strange creatures. With one man down you escape that hell and move on.

Now you are called to Nevada because something terrible happened there (see Area-51) and it affected the nearby city. But you soon realize, that all this has something to do with what you encountered inside the bunker three years ago.

The game is a pretty straight-forward first person shooter. You move through the levels, kill everything that moves and fulfil your objectives. To aid you in that task, you've a squad full of people under your command. With the help of cursor-sensitive commands you order them around and let them man a stationary MG for example. But there are also marked points in the levels at which your squad will perform scripted tasks like a door breach.

Depending on the difficulty you need to watch the moral of your team mates very carefully. While a high morale will make your squad very aggressive and increase their aim, they'll take more cover and be less accurate when they don't feel so confident. To increase morale you just need to do a good job or give your team mates a common target to shoot at.

The game also features a multiplayer-mode with several game modes. These include Deathmatch, Team Deathmatch, Capture the Flag and Abduction. In Abduction there are two teams: the humans and the Reborn. One player randomly starts as a Reborn and whenever a Reborn kills a human, the human will respawn as a Reborn. For such a kill a Reborn gets two points and all surviving humans gain a bonus point. After all humans are abducted, the round ends and the player with the most points wins the match.