Lahr (Automatic Vaudeville, 1984, etc.), in British tonalities never learned from his father, offers an overwrought backstage bio of a comedian largely unappreciated this side of the Pond. Self-proclaimed mega-star Dame Edna Everage (My Gorgeous Life, 1991) is a confidante of royals and a hobnobber with international glitterati. Surely, there's nothing like this Dame, with her contempt for her fans and the ``paupers'' in the balcony. (She skewers her ``possums'' lovingly, she says). The ineffable dominatrix from Melbourne is, of course, a pantomime lady—that favorite of the otherwise explicable British, a comic in drag. The Çminence grise inhabiting Edna's pantyhose is one Barry Humphries, a randy comic from Down Under. Humphries, a complex, self-centered, and often hostile man (it's said lovingly, possums), is a music- hall artiste of multiple personalities, including Edna's opening act, Sir Les Patterson, also from Australia and a souse with a stupendous appendage. (In ``the area of phallic fun, Sir Les holds his own,'' Lahr notes with his British humor, but he's ``not everybody's cup of pee.'' Be warned.) Undeniably, Humphries has a quick and unique wit that can steer the Everage faux gentility through jokes about leprosy and her late husband's prostate. But Lahr's sappy adulation veers toward parody itself. The ``excesses of Humphries' temperament,'' he gushes, ``are forgotten in the face of the abundance of his talent,'' even as his subject repeatedly gives him the brushoff. Humphries ``strides past me,'' Lahr notes. ``After another few minutes it's clear that I will not be summoned.'' The feckless author is happy, though. He just wants ``to stop time and to chronicle a moment in the prime of a great clown's life.'' ``Barry Humphries is among us, and he is the goods,'' insists Lahr. It remains to be seen if these goods will sell in these former colonies. (Photographs—not seen.)