Conceived as a farewell performance before Bond goes to London for a year to study at St. Martin's College, the three-hour Carnegie concert served as a rollercoaster recap of the gnarled club circuit veterans' years in showbiz. It also proved the final step up the evolutionary ladder from novelty act to flesh-and-blood characters with a seething, snarling, scary life of their own.

For the uninitiated, Kiki (Bond) is a sixtysomething lounge singer who sloshes her way through one comeback show after another, getting progressively more oiled on Canadian Club, and Herb (Mellman) is the melancholy accompanist she met in a childhood institution and has been performing with ever since.

Their shows consist of an anarchic grab-bag of covers spanning hip-hop to power-pop, funk to punk, art-rock to spoken-word rants, all put through Kiki's lacerating blender of a larynx to come out sounding like deliriously overwrought torch songs. Numbers are punctuated by lengthy digressions as Kiki ruminates bitterly on personal history, politics, self-sacrifice and shattered dreams.

While there were no significant departures from the duo's formula, perhaps the most surprising aspect of the Carnegie show was how thoroughly Bond and Mellman have shaped what could have been merely a best-of self-feting into a soul-searching journey with a muscular theatrical arc -- far more even than last year's Off Broadway stint "Kiki & Herb: Coup de Theatre."

Kiki's tragic reminiscences take on a resonance here that works in rich tandem with the savage humor. Barry Humphries also developed his female alter ego, Dame Edna, into a fully fleshed-out figure replete with family history. While Edna is a grotesque caricature, however, Kiki is no less monstrous yet somehow more human in her angry, booze-sodden fragility; as a theatrical creation, she transcends drag. The estrangement of her gay son Bradford and ever-absent daughter Miss D -- who actually turned up this time after years of no-shows -- her Stepford-wife meltdown and attempted murder of her husband and the drowning of her daughter Coco off Monte Carlo are both blackly hilarious and oddly affecting.

While in lesser hands Kiki might seem an unlikely conduit for a political agenda, the singer's laceration of the current White House administration and her refusal to accept "the legacy" of Ronald Reagan as endorsed by the mainstream American media seem an organic part of her jaded worldview.

Herb's troubled background has featured more extensively in shows past, but Mellman seemed content at Carnegie Hall to sit back and let Kiki take the wheel. He grabbed the solo spotlight in only one number, the Decemberists' "I Was Meant for the Stage," while Kiki lay comatose after her harrowing, trippy rendition of "The Windmills of My Mind."

But Herb is by no means just silent backup. In addition to wailing harmonies and hammering the Steinway uninterrupted throughout the set, he coaxes Kiki through her more traumatic episodes, urging her to move on and forget.

Musically as well as theatrically, Kiki & Herb have become increasingly inventive and audacious. Any performers who can find the fluid throughline in a medley that morphs from "The Rainbow Connection" to "Tomorrow Belongs to Me" to "Edelweiss" are not just fooling around with campy satire.

Even more ambitious and musically eclectic was a segue from Gil Scott-Heron's "The Revolution Will Not Be Televised" to Eminem's "Lose Yourself" to Talking Heads' "Once in a Lifetime" to the Singing Nun's "Dominique." Latter ditty leads to a reflection on showbiz martyrs, ranging from said nun to Marlene Dietrich to "Our Lord and Savior Jesus Christ, who died so Mel Gibson could be a billionaire."

As the evening wears on and Kiki's composure erodes, the decrepit diva's braying interpretations inch under the skin with their unsettling mix of self-reproach and fierce accusation. Especially memorable were Marc Almond's bitter "A Lover Spurned," a torn-up version of Joy Division's "Love Will Tear Us Apart," a taxingly calisthenic take on Tom Jones' "Sex Bomb," Style Council's rueful "Paris Match" and the cheesy Bonnie Tyler hit "Total Eclipse of the Heart," performed as one of several encores, with brief detours into Pat Benatar, Yeats and Joni Mitchell.

Several guests joined the performers onstage during the encores, including vocalists billed as CC and Ginger (Micki Fagerberg, Myra Schiller) -- whom Kiki claims to have met in rehab ("a nice little vacation, and it doesn't last long") -- providing spirited backup on Melanie's "Lay Down"; and a posse including Rufus Wainwright, Sandra Bernhard, Isaac Mizrahi and Jason Sellards of the Scissor Sisters on "Those Were the Days." Despite the seeming reluctance of the capacity crowd to hit the exits, Kiki closed the evening firmly and poignantly with a wistful take on Kate Bush's "Running up That Hill."

"If I could love, I would love you all," Kiki cooed at the close of the show. For the Carnegie audience, there was clearly no such proviso. If the New York concert marked the death of the reprobate duo, bring on the reincarnation tour.