You must be at least 21 to enter the groove (note the hip lowercase lettering), a cavernous hall where every nook and cranny is filled with techno pop. The very sound of the place can be terrifying to the uninitiated: images flicker rapidly on several screens and the combination of music, light, and mayhem appeals to an under-30 crowd. They know enough to escape the dance floor into three rooms: the '70s-style Green Room, filled with beanbag chairs and everything you threw out when Duran Duran hit; the sci-fi Blue Room; and the Red Room, which is hot and romantic in a bordello sort of way. Prepare yourself for lots of fog, lots of swirling lights, lots of motion.