Happy! Sad. H-h-h-happy! Sad. You know those theatrical mask things, one with a smile big enough to house a Manic's packed lunch, the other with a frown deep enough to please a Manics fan? That's tonight, that is. Or maybe tonight's more like a fortune cookie in reverse: the unpalatable, paper-thin, trite message stuff first, and the tasty, crunchy bit to follow. Whichever way you look at it, there's something very schizoid about this bill. Happy! Sad. H-h-h-happy! Sad. Pulp...

EELS. Eels are just sad. They play the Stones' "Satisfaction" and it packs as much punch as the sound of Capital Gold drifting from a pensioner's rickety old Morris Minor. They play their own songs and it just feels like someone's left a tinny transistor radio crackling static onstage, the distant mumbling of a talentless cipher. Three seconds of "Climbing To The Moon" are moving (fair's fair), but the rest is dust, singer E hovering motionless by his mic like he's waiting for a bus to come. The buses are on strike tonight. Sad, sad, sad, sad, sad...

Happy! That's PULP, right? Well, no - not this year, it isn't. You know the story (bad sales, bad moods, bad hair), but no one knows the solution, do they? How do you promote an astonishing album of experimental miserabilism like 'This Is Hardcore" with a f***ing smile on your face? How do you walk onstage singing "The Fear" and camp it up for the pop kids? It's impossible, right? Well, no, not quite...

Dancing in front of a nifty inflatable mattress backdrop is one Jarvis Cocker. To his right is Jarvis Cocker. Two Jarvis Cockers? Yup: one's real, one's an impersonator. They're both singing "The Fear", both shimmying about to the ominous throb of the music, but only one of them's saluting and leaping and doing that weird angular-twirly-pointy thing with his index finger. He's the impersonator. The other one's the genius, a genius because he's letting his doppelgänger do the clichéd Happy! Pop! bit for him, just like he let E do the clichéd sad, experimental miserabilism bit for him earlier. Jarvis is making sure everyone gets exactly what they want tonight ("they used to be such fun"/"they're brilliant now they're bleak") - but not from bloody him, thank you very much. And that's just inspired.

The trick comes once we start seeing single again. When all there is left is Jarvis and us. And the songs, and the show, and the effort, and the conviction and the soul. Not the band, mind, though they back him better than ever through the frantic, anthemic sounds of "Sorted For E's And Wizz" and "Party Hard", Pulp personnel numbers two through six skulk unseen in the shadows tonight. Which leaves Jarvis to harmonise that schizophrenia all by himself. Which leaves Jarvis to become a star again.

Which he does almost straight away, by playing "Babies" and making it sound new, rooted to one spot by dint of his guitar, expressing everything with one eyebrow, one voice and one intention: Look At Me. Which we do, throughout a quivering "Joyriders" and an unblemished, milk-pure "TV Movie"; throughout a swollen "Sylvia", his body telling the story, another flick for each feeling, Braille for each beat, semaphore for each sound. So new songs like the staggeringly jagged "This Is Hardcore" mingle seamlessly with old ones like the jubilant "Underwear" without an iota of discrepancy, without the slightest sense that the inclusion of songs like "Disco 2000" and "Common People" in the set is merely to appease the recently repulsed.

And why? Because, to be honest, the songs just don't matter tonight. They're brilliant - each and every one - because of who's singing them, and how. You think there's no dignity doing a predominantly greatest hits set? There is if the greatest hit of all is yourself. So tonight's joy comes through watching Jarvis' reclamation of his character, his rediscovery of that uniquely flippant rebel stance; mocking the new instant-expulsion-for-drugs-at-school rules with a tabloid-goading sass, introducing the worryingly themed "Help The Aged" as "F*** The Aged" with a resurrective undertone, with a wink that reads: "Sorry, I just got bored being me for a bit. But I'm back now. I'm back." There's the joy: he's back.

So, as an almost ironic "Something Changed" sends us home, the common people disperse to the "Gym And Tonic" bar (how pop is that?), the hardcore glumsters to their dusty coffins and Radiohead albums - but everyone's content. And Jarvis? Jarvis just skips offstage to share a beer with his looky-likey. Because he's comfortable with himself again. And we're all comfortable with that.