The Clean House was a play about the importance of getting filthy, and no play in the last year or two has enjoyed a set that so perfectly captured its theme. Beginning as the oppressively clean domicile of a couple of doctors, by the end the stage is an irreparable mess — or so it would appear; since they had to repeat the process several times a week, the irreparability of the cast's wanton destruction was probably an illusion. At one point, the house gave way to a two-story beach bungalow hiding behind it: as one of the doctors and his paramour partied on the bungalow's balcony, they loosed both symbolic and actual detritus on the ever-filthier home below. Later, the house suffered the further indignity of having an uprooted yew tree dragged through the living room. The place was so sparklingly sterile at the beginning that its slow destruction was physically painful to watch, like seeing somebody get deflowered. But it was also liberating. Which was the point.