When Liverpool's most grandiose post-punk scally-delicists released their fourth album, Ocean Rain in 1984, it was advertised as the greatest ever made. Despite this provocative hyperbole from their manager Bill Drummond - something he would perfect during the career of the KLF - it wasn't, but it was the sound of a very good band at the peak of their powers. It was also the last time the original four members ever sounded so special or produced a work that was both so fragile and so heartfelt.

To hear Ocean Rain live then, complete with The Cairns Strings sextet bolstering original vocalist Ian McCulloch and guitarist Will Sergeant should be something indeed. Indeed it should be an event on a par with the original Crystal Day concert in 1984. This was an all-day magical mystery tour around Liverpool including a bike ride, breakfast in a diner and the inevitable ferry cross the Mersey, before a three hour concert at St George's Hall; all of which demonstrated just how far the four piece had come from cutting their teeth at Eric's.

The cellar club cum social experiment called Eric's run by Roger Eagle, Pete Fulwell and Ken Testi on Matthew Street, was a stone's throw from where the equally underground Cavern club had been filled in and had a car park built over it. In Liverpool at least, it was the epicentre of punk, post punk and synth pop, and provided a shelter of sorts for every freak in town. Echo and the Bunnymen, OMD, The Teardrop Explodes, Pete Burns' Nightmares In Wax, the legendary Big In Japan and Pete Wylie's Wah! were just some of the success stories to stumble out of its sweaty interior, blinking into the light of success beyond the confines of the club.

Thirty years ago Eric's was closed down following a police raid during a Psychedelic Furs gig; but not for good. A new theme park version of the venue, built on the same site, has opened its doors. In terms of authenticity it is in keeping with the similarly rebuilt Cavern Club which stands across the way on the tourist trap of Matthew Street.

But would Ocean Rain played live 27-years after the St George's Hall show be a similarly grotesque act of nostalgic vandalism? Or would it tap into something bigger perhaps - a spirit of vindication for all the dole-queue dreamers of Thatcher's Britain who found their own way to the stars with this album as the sound track?

Glasgow is the ideal city in which to see the show given that this was where the first-generation Bunnymen ended it all after a show at Barrowlands. The concert is in two halves, the first, a hits set and then, the album we're all in attendance to hear.

Immediately, however, alarm bells begin to sound and it isn't because of the band. During opening number 'Rust', Will Sergeant stands to one side as diffident as ever, lit by a bedside lamp as he carves gloriously minimalist solos from thin air. He provides an understated sheen to the generic melancholy of this second-generation Bunnymen anthem. It's Ian McCulloch who appears off-kilter, his delivery... faltering. Despite constant signals to the sound-man, on the song's conclusion Mac indulges in a rare moment of near humility when he admits his performance to have been “a bit shaky... one point off the ten”. Sadly the score is set to get considerably lower over the next two hours.

'Rust' is followed by a bombastic version of 'Pride', b-side 'Stars Are Stars' and then more recent material. McCulloch tries to encourage the crowd to stand up, threatening to sing 'Donald, Where's Your Troosers?' before muttering how The Beatles were actually Cockneys and then moving on to an impromptu impression of "Jim Morrison impersonating Sid James". It appears Mac may been drinking. He rambles on at length about cake. He has been given chocolate cake which he does not like. It is the 16th birthday of one of his string section. His slice of cake had a candle on it. Something else that he does not like. This diverse monologue will at various points in the evening cover allotments, how Glasgow Barrowlands saved his life, how Geordies sound like knobheads and how he nearly got expelled from school for setting his hair on fire. And some of it will be conducted in a Scottish accent.

During 'Bring On The Dancing Horses', 'Bedbugs and Ballyhoo' and more recent fare a steady flow of booze flows past McCulloch's lips. And, while the band sound ever more urgent on Never Stop and Rescue, the front man pretty much ruins the latter with a barrage of verbal diarrhoea that one might associate more with Jimmy Tarbuck or Stan Boardman rather than a rock legend.

As for the singing, when McCulloch's not missing the high notes, it is pretty much left to the audience to fill in the gaps. And 'The Cutter', 'The Back of Love', 'Nothing Lasts Forever', 'Lips Like Sugar' are conspicuous by their absence. One hopes they and all the rest will be saved for the encores. But there is to be no such luck.

The Ocean Rain set itself starts well, ushered in by the triumphant opening flourish of 'Silver', and for a few minutes the elegant majesty of the album sounds reborn as it soars into the woozy drama of 'Nocturnal Me'. The poppier tracks rein him in awhile, but the loose-knit, proto-Grinderman fury of 'Thorn of Crowns' allows him to indulge himself in an increasingly infuriating fashion. Always one to believe his own self-deifying bullshit, McCulloch's patter grows in turns tiresome, self-indulgent, self-pitying and self-aggrandising. Then it becomes aggressive, offensive and downright abusive. Things start getting really ugly when he starts threatening hecklers with violence, perhaps not getting the fact that the aggrieved objects of his derision might feel somewhat short-changed by the debacle considering they've shelled out forty quid for a ticket.

Then, remarkably, it gets worse. Even the laptop working the filmed backdrop messes up. Yet, all the while the band power on regardless, through a botched opening to 'The Killing Moon', which McCulloch blames on the audience clapping out of time. The full version of the song is even more painful, making one wonder why McCulloch introduces it as “the greatest song ever written” if he's then going to talk nonsense over it about how Liverpool and Glasgow have the best accents in the world.

'Seven Seas' is a mess, which, again, the audience do most of the vocal work on while the band attempt to salvage something from it. There are flashes, especially on 'My Kingdom', when the Mac of old comes into view, but largely this is sad, self-parodic stuff. “Sorry about my appalling behaviour,” he slurs, “but I can't remember what I did.”

'Ocean Rain', the album's title track, and most beautifully heroic song, collapses before it starts. People are angry now, and McCulloch, a sneering, nasty drunk, his voice shot, taunts them even more. For a moment it looks like something might kick off, but after assorted threats, McCulloch stumbles offstage, unable to get it together, like it's everyone else's fault. He comes back on, but he shouldn't have bothered.

He says something about receiving bad news but if this is the case, then why did he, or anyone else involved, let the gig go ahead? He attempts yet another stab at 'The Killing Moon'. He barely sings a note of it, opting instead to furiously try and explain the song's meaning, babbling about death in-between sparring some more with the crowd.

If all this wasn't troubling enough to watch, McCulloch, still looking for someone else to blame, ambles over to Sergeant, berating him for something he apparently didn't know about, but which the band – or was it the audience? - did. After lobbing a bottle at his band-mate of more than thirty years, McCulloch leaves the stage for the final time.

As things peter into a sense of disappointment and anti-climax, perhaps Sergeant is pondering throwing his lot in with former Bunnymen bassist Les Pattinson. He came out of musical retirement to join a re-ignited version of their early eighties support act, The Wild Swans. Currently knocking them dead in the Philippines, it should be remembered that the sole Wild Swans release during their original, all too brief life-span, was bank-rolled and produced by original Bunnymen drummer, the late Pete de Freitas.

Sergeant has played live with The Wild Swans already in Liverpool, and also features on the band's just-released album, The Coldest Winter For A Hundred Years, an album which possibly says more about Liverpool than any other recorded.

As far as McCulloch is concerned, his gobby bravado - much like his shades - has always been a front to hide his shy vulnerability. This side of him only fully came out on the band's 2001 Flowers album, an uncharacteristically reflective mid-life statement. Whatever is troubling him tonight however, one can only hope its an anomaly or something that can be straightened out easily by friends and family.

If it's not serious, and is just a bad night on the piss, then shame on McCulloch - he's old enough to know better. He needs to have a word with himself and remember that all of his rock & roll heroes were either dead or clean by his age. The posters in the foyer for a forthcoming sixties revival tour featuring first generation Merseybeat groups Gerry and the Pacemakers and The Searchers may look like incongruous cabaret compared to McCulloch's display, but at least they know how to keep it professional.

As for Echo and the Bunnymen, the band and the Cairns Strings were awesome, and deserve medals. The band's singer, figure-head and auto-didactic genius, alas, cut a tragic dash, however fascinatingly, horribly watchable he remained. Like the man said, bring on the new messiah. For now, at least, this one is seriously all at sea.