Xbox 360 | PC

"BioShock" is banned from Valve Studios. The team behind the legendary first-person shooter "Half-Life" has declared that none of its employees is allowed to touch the game. Managing Director Gabe Newell explained to computerandgames.com: "Nobody gets to play it until Orange Box is done—that's our reward to ourselves as a company; everyone gets a copy of 'BioShock." When Valve openly praises another company's FPS, it becomes clear that something has gone very, very right.

I sat down with an Xbox 360 and a copy of "BioShock," spiritual successor to the "System Shock" series, and for the next week explored the city of Rapture, an underwater utopia created in the aftermath of World War II in an attempt to escape the powers that governed the world at the time. The game is heavy on symbolism, deeply influenced by the works of Ayn Rand and the philosophy of objectivism. The player, caught in a plane wreck near the entrance to Rapture, finds himself in the middle of what looks like a civil war between Andrew Ryan, mysterious ultra-capitalist and founder of the city, and the few residents who have retained their sanity.

"BioShock" is more than just an FPS, throwing in elements from the adventure and role-playing game genres. The player explores the dozen or so levels, gunning down enemies, hacking into security systems and learning, through recordings and radio transmissions, the truth behind the ruined city. Genetic modifications, in the form of "plasmids," allow players to customize their character—specifically in terms of combat.

Some plasmids allow you to freeze, burn or shock your foes. Others grant you telekinesis. One particular plasmid turns the player's left arm into a functioning, controllable hornet's nest.

Despite the wide range of ways to kill your enemies, the combat could be better. Honestly, most enemies are fairly similar (their attack methods are the major difference) and midway through "BioShock," you'll find that conventional weaponry outclasses even the best plasmids available.

Despite the flaws in "BioShock," the game is a cut high above the rest. The world is believable and immersive. The setting is the late '50s, and every aspect of Rapture seems authentic: the dress, the design and the ideology.

The game is also superb technically. There are almost no errors or glitches, the controls are completely natural, and the game has an overwhelming feeling of completeness. Invisible walls are non-existent in Rapture. Every bit of what you see, you can explore. Your character is free to conquer the forces of the lost city with whatever means necessary, and that sort of control makes for an incredible game.

All of the dialogue in "BioShock" is voiced by professional voice actors, from Atlas' heavy Boston drawl to Ryan's socialite sneer. Characters you never meet can develop an entire persona in "BioShock." The ambient sounds range from the whispers of an insane splicer to the low, dull roar of a Big Daddy, the game's strongest opponent. With its sounds, Rapture accomplishes what many video-game cities don't: not only does it sound like it's alive, it sounds like it's dying.

"BioShock" is a step forward in gaming. It's an impressive effort by a dedicated team, and it does its spiritual predecessors justice.