From what you've seen and heard of it up until now, you may think Bioshock is a complicated beast. Ken Levine, Irrational Games' Creative Director, thinks otherwise. "At its core," he tells us, "Bioshock is about giving players cooler ways to do nasty shit to enemies." He's right, of course - you can do some nasty shit to enemies. But reducing the game to such simple terms is like saying the White House puts a roof over the president's head. Because Bioshock is much more than that. So much more it may even be about to redefine the whole genre.

As you may be aware by now, Bioshock takes place in Rapture - a haunting Art Deco-tinged underwater city. It's a triumph of imagination and a timely, deliberate reaction to the familiar environments of military bases, space stations and identikit future cities that so many other games developers insist on incorporating. The story is a bold one, unafraid of weaving themes of responsibility, human conflict, Capitalism, slavery and extremism. It confronts you with moral decisions that change your perception of the world. And, naturally, it gives you a huge range of attacks that use the environment and other characters, and customizable weapons and powers that, well, let you do a lot of nasty shit to your enemies.

"Shooters are great and they're exciting but they're the same for everybody. The same monster pops out at the same time. Bioshock is very unpredictable. I think it's going to be really striking for the gamer," Levine tells us. Its unpredictability comes from the spectrum of choices that you'll make, and your interaction with Irrational's fresh approach to NPCs.

Enemies aren't spawning from specific points with explicit instructions or reactions. Instead an AI eco-system operates where behaviors and emotions, not set routine, guide Rapture's inhabitants. They really exist in this world, so they'll really react to you based on your past behavior; they can use any weapon that happens to be in their vicinity to take you on and they can roam Rapture's eerie halls as they wish. Irrational may have made the characters, but as Ken himself admits: "Sometimes we don't even know where they're going to be."