Oasis Landsdowne Road, Dublin ****

Ever since the days of their Britpop infamy, Oasis have resembled something between a macabre drama and a deranged soap opera. The recent episodes alone would keep Coronation Street scriptwriters in jobs for several years: rhythm section quits in acrimony; rejigged band release "classic" comeback album; songwriter (Noel Gallagher) admits "classic" comeback album is crap; a feud over "lifestyle" prompts a newly drug-free Noel to walk out in disgust; wildman brother, Liam, and a cobbled together Oasis tour Europe without him. Impeccably and inevitably (and following tabloid stories of touring benders), the day before his crucial homecoming(ish) gig, Liam's wife (Patsy Kensit) walks out.

So it's hard to know which is the greater surprise: that Noel is back, or that brother Liam is still with us. There is an argument which says that minus three of their original lineup, Oasis will never be the force that spawned Definitely Maybe. Few bands could withstand such losses, but Oasis are one of them. This is partly because of the simple construction of their music but mainly because of the fearsome charisma of the Gallaghers.

For the first few numbers this is all that sustains them. Liam, surprisingly, cuts a more mature figure than the boorish lout we have loved/hated, and Noel's stony face holds an entire storybook. Hampered by high winds and poor sound, Who Feels Love, one of the only three cuts from Standing On The Shoulder Of Giants, all but blows into the sea. However, as a sliver of a grin creeps across the senior Gallagher's face, Oasis deliver.

The key is Acquiesce. This song of brotherly togetherness has never sounded more inappropriate, nor more poignant. As the younger Gallagher finishes hurling out the lyrics, he announces: "Don't believe what you read in the papers. We're not splitting up." The crowd roar and Liam walks across the stage to shake his brother's hand. From anyone else, this would have seemed absurdly scripted, but this sincere moment proves the turning point in the gig.

Playing Shakermaker, Stand By Me, Wonderwall, Oasis seem to be rediscovering what had made them good. Although there's something curiously dated about the (mainly male) audience's sea of casual tops, these ageing sing-along songs take the wider canvas and the band fill in the details. Cigarettes & Alcohol is rather mischievously dedicated by Liam "to Blair's son, I think it's brilliant". Inevitably, Noel chips in. "This one's called Rock'n'Roll Star, and we are," he says, attitude undiminished by his regretted two years in the Met bar.

Occasionally, the band reach the heady heights of their classic 1990s Maine Road shows. Noel seems genuinely moved when the crowd sing Don't Look Back In Anger. Most strikingly, a young fan dances precariously on the roof of the mixing desk tent during Live Forever, risking everything for a glimpse of immortality as the band's anthem is accompanied by gasps from the crowd.

Heavyweight stuff, but questions remain over Oasis's own lifespan. Can they rediscover this spark on record? More to the point, will the senior Gallagher remain? Noel's solo performance of Neil Young's Hey Hey, My My (Into The Black) with the lyric "It's better to burn out than fade away" seems unusually provocative. But this would be a curious time to bow out. Far from the expected Tysonesque freakshow, Oasis sound like a great band limbering up for another shot at the title.