TORONTO - When future rock historians look back on the life and work of Iggy Pop -- and they will -- they'll no doubt be as fascinated by his checkered career as they are by his indestructibility.

The artist otherwise known as James Jewel Osterberg knows how to keep 'em guessing, and, while his last bunch of records haven't exactly been classics, he could hardly be accused of repeating himself.

That is, until you get him up on stage.

As the 52-year-old singer proved yet again at The Warehouse Saturday night, some things need to be repeated -- repeated loud and fast.

Iggy is ageless on stage. Impossibly well-preserved given all that self-inflicted wear-and-tear that made him a proto-punk legend, he seems locked in time, wriggling and flailing, shirtless and shaggy-haired, as if temporarily repossessed by the same demons that nearly killed him in the '70s.

Decades-old songs -- 1969's I Wanna Be Your Dog, '77's Lust For Life, some Stooges, some solo -- sound as if they're being discovered on the spot. The sinewy singer's in a state of catharsis, which he transfers magically on to some 1,500-people in the crowd -- at least, those lucky enough to be in the first 30 rows.

What might seem pathetic coming from a less fine-tuned rocker seems like an intense musical pilgrimage. Sure, rock 'n' roll fans are a forgiving lot and they love to relive the past -- which explains why everyone from The Rolling Stones to Styx are still around -- but Iggy obliges them tenfold by not just going through the motions.

The Warehouse did get a taste of Iggy the modern guy, too.

New album Avenue B is a dark and reflective effort inspired by his recent marital split, complete with moody ballads and spoken-word pieces.

Iggy's decision to open his show with one such song bordered on concert hara-kiri. Imagine the expressions in the rowdy Halloween crowd as Iggy launched into his set by telling them about "the winter of my 50th year."

But, as Iggy and his backing band of hair-metal types broke the tension and brightened the mood by tearing through back-to-back versions of The Stooges' Raw Power and Search & Destroy, the introduction made sense. Behind all the bombast, there was a dark side and it was only fair that he let us know about it.

The singer did pause between latter-day crowd-pleasers Real Wild Child, Home and an apt cover of Johnny Kidd's Shakin' All Over for a bit of motivational chatter, but that was unnecessary in light of, say, a gripping piece of rock 'n' roll joie-de-vivre like The Passenger. Between stage-dives, the Iguana even managed to haul a platoon of stooge-auxiliary onto the stage for a sing-along. (Suitably, there was one woman there out of some 12 men, which was a pretty clear reflection of the audience demographic).

Iggy toned it down again in the encore with new tune Miss Argentina, a worthy crooner that he performed alone on his knees with an acoustic guitar (!). Then, the ultimate blow: An eyelid-shaking stream of Stooge-era noise that included TV Eye and the rare beauty I Got A Right, plus the staple Louie Louie.

The only shame of the night was the fact that jazz combo Medeski, Martin & Wood -- featured players on Avenue B -- happened to be performing next door at the Guvernment but didn't stop in for a jam as rumoured. But then, Iggy had things pretty much covered all by his own old self.

JAM! Rating: 4 out of 5