Izzard roams across the cosmos and through the centuries in search of a theme. Occasionally he actually finds one and finishes his thought -- on the intrinsic nature of religions, say, or the links joining monkeys, Charlton Heston and guns.

It's not the decisive conclusions that matter (``Aristotle was the Homer Simpson of philosophers''), but how Izzard gets to them. Or better yet, how he gets cheerfully lost along the way. A listener couldn't begin to retrace the steps from ``Pope Johnny Paul II'' to ``Baywatch'' on the English Channel to a bar full of card-playing dinosaurs. We're all just along for the fun ride inside Izzard's brain.

Some of it's cerebral and tightly packed (a compressed history of post-World War II global politics). Some is conventionally gag-structured (an obscene twist of Margaret Thatcher's knickers). Think a British, non-Jewish Jackie Mason -- who also happens to be a transvestite -- and you've got a rough fix on a good deal of Izzard's humor.

But the 38-year-old comic stretches that envelope and tears it open. He segues into a kind of rational surrealism -- Puccini's ``Nessun dorma'' and a swinging corgi are the reasons for the Queen Mother's missing tongue. And his physical humor, which he tends to employ stealthily from an otherwise stationary position, is a key weapon in the arsenal.

Izzard can switch smoothly into parodic high gear when he catches himself striking a soap opera actor's pose. His impression of an all-drug Olympics (``The best chemist wins!'') cries out for an instant replay.

Izzard affects a slatternly, spine-sagging posture in his tight trousers and wide-lapeled blouse and uses that slackness coyly: A conspiratorial grin blooms across his wide jaw. An elbow shoots out to illustrate a killer swan's technique. He staggers through a stoned high jumper's game approach to the bar and wilts in sudden ``F-- all'' indifference.

``Circle,'' which is still under construction, is not as polished or engagingly varied as ``Dress to Kill,'' his 1998 West Coast debut show at the Cable Car Theatre. Izzard made a gag out of noting the bits that weren't working at Wednesday's opening; some pruning and shaping are still in order. A suggestion: Lose some of the references to ancient TV shows.

Nor is this the outrageous confession of Britain's most famous straight funnyman in women's clothing. This time around, Izzard offers nothing about himself or his past. His garb is positively restrained. Aside from the lipstick, lacquered nails and high-heel boots, he might be any bloke out for a night at the disco.

Tucked inside Izzard's off-kilter glam look is an overgrown kid who's read a lot, stayed inside to watch too many TV documentaries, stewed in his own fevered juices and cooked up crackpot theories. There's a bit about Venn diagrams, which may be a stand-up comedy first. He's fascinated by dinosaurs and the Spanish Inquisition and assorted other outsized oddities of history. Even Izzard's sailor-look blouse vaguely suggests the school uniform of a gawky, brainy child.

Not that Izzard's humor isn't fully worldly and grown- up. He talks about politics, philosophy, cosmology and finishes up with a riff on transubstantiation. For Izzard, serious subjects call for the most unlikely comic connections, with a shrug to fall back on.

In the midst of a detailed explication of international feuds, Izzard pauses to reflect on why the self-satisfied French didn't hate the insecure English: ``They couldn't be bothered.''