View Slideshow __Looking for a relaxing __vacation spot? Come enjoy the refreshing undersea dystopia of BioShock, a highly anticipated game for Xbox 360 and Windows. From the moment you arrive, you're plunged headfirst into an objectivist social experiment. Banners proclaim ALTRUISM IS THE SOURCE OF ALL EVIL, and perky advertisements preach the wonders of genetic modification. The architecture is all Albert Speer does art deco (A), but the world, called Rapture, is beginning to crumble and let in water. You're soon beset by deranged flappers and dandies, like Jay Gatsby's party guests gone feral (B). And, as in any first-person shooter, you reach for your gun...

Or do you? It's just the kind of ethical question that bubbles up from the depths of this game. "We're living in a very gray age," says Ken Levine, cofounder of Irrational Games and lead designer on BioShock. "When I play an ultra-patriotic game, I'm not comfortable unquestioningly accepting what authorities say." Players are bombarded with radio messages from Rapture's rival warlords, all offering conflicting advice. Will doing what they say help your cause or merely advance their own agendas?

Or consider the Little Sisters and Big Daddies (C). The Sisters are hollow-eyed creatures who search out corpses as a source of genetic material - the coin of this twisted realm. The Daddies, lumbering monsters in diving suits, are their vigilant protectors. Defeat a Daddy and you can set the little girl free — or steal her genetic bounty and use it to enhance yourself, killing her but prolonging your own life. Which would you choose? "I like making games where the player has to figure out their own path," says Levine.

Online Extras Slideshow: The Dark Descent