Why is it called Thursday? That's the funniest mystery in Adam Bock's mysterious new play about a gay man snubbed by his boyfriend and a faded TV star snubbed by her hometown. The set shows a pure white interior of a house, furnitureless, with flower shapes of colored light turning on the walls. The look is almost as funny as the burpy, poppy, '60s-bubblegum soundtrack. Pete's brother George is going out with Alison, who's jealous of Marcy because Marcy used to go out with George. Charlene and Janet, a pair of lesbians, try to keep Alison from killing Marcy, while Pete makes himself an irritating hypochondriac after his ex-boyfriend Jimmy goes out with a guy named Alex. Got that? If not, don't worry, because Bock hasn't written a drama rich in character but a musical piece of textures and rhythms, rapid back-and-forth exchanges, repeated sounds, and stylized movement (by Mark Jackson). Some of it's good-humored and infectious, some of it's overwrought and underacted; the whole thing is delightfully meaningless, like a Pinter play crossed with a Seinfeld episode. "What do you do when people don't want you anymore?" asks a tag line for the show, and Bock's answer seems to be: cause a lot of silly pandemonium, and then get over it.