Little does Stan Kraychik--``master hairdresser, poetic wigmaker, irksome homosexual''--know when he arrives in the Boston suburb of Abigail-by-the-Sea that Verdi's Un ballo in maschera, the inaugural production of the new Sidney Blaustein Center for the Performing Arts, is about to be upstaged by offstage intrigue, back-stabbing, and murder: The set designer, the newest object of insatiable stage director Sir Jonathan Byers's lust, is brained by a computer-driven scrim. If only the victim had been homophobic, tone-deaf diva Marcella Ostinata, laments Stan; and lo and behold, the next victim is. Lucky Stan even gets his wish again in re the third victim, by which time tempers are short and lists of motives long (Marcella's understudy blossoms in the spotlight; a secret marriage is revealed; so is an unacknowledged child of la tempesta's by the late Mr. Blaustein). Mostly, though, what supervenes is endless rounds of suitably bitchy backchat, with the characters graded up or down according to their homophobia, their success in coming out of the closet, and their own sexual practices (``When is penetrative sex ever really pretty?'' muses Stan of Sir Jonathan's boy toy). The operatic setting, with its hilariously precise caste system of attitudes toward homosexuality, is as ripe for Michaels (Dead on Your Feet, 1993, etc.) as it was for the Marx Brothers-- and the finale even squeezes a little of them in, too.