The set design in the first act of this elaborate comedic drama about the proto-pack-rats Homer and Langley Collyer is impressive enough, a stately Brooklyn mansion oozing wealth and containing the subtlest, earliest signs of hoarderdom. By the time you return to your seat after an unusually lengthy intermission, you witness an epic transformation that looks like it was an art project months in the making. The act takes place nearly two decades later, and instead of anachronistic opulence, the Collyer abode is a nightmare of domestic debris: Filthy newspapers stacked to the heavens, broken lamps scattered about, furniture completely inaccessible. The clutter is convincing, the detritus staggering, the result almost magical. Michael McKeever, Nicholas Richberg, and Marckenson Charles do a fine job of performing in a claustrophobic space in front of this display, but the set was the show.