Two tales of a city. Of Dublin's fair city, where the girls are still quite pretty, though the Georgian squares aren't what they used to be and it's easier to find an overpriced "traditional Caesar salad" than cockles and mussels, not to mention an honest Irish stew.

The first tale concerns Conrad Gallagher, once a purring tiger of the hyped Celtic economy, and now a disgraced ex-celeb. His rise had been meteoric. In his mid-twenties, Gallagher was hailed as "Ireland's only superchef", and "the new high king of Irish cuisine". Bono and Sting ate with him and partied afterwards. He was given to self-promotion and lofty pronouncements: "Food should be like grand opera," he swanked.

Critics who enjoyed his dishes spoke of "a torrent of ideas", or of his "wacky combinations, constant inventiveness and utter confidence". He bragged that he liked food with "four or five flavours on a plate", food without " boundaries", "height on the plate" (which translates as those teetering, multi-layered towers). At his Michelin-starred restaurant, Peacock Alley, Gallagher was famous for his seared scallops and langoustine ravioli; and, this being Dublin, for his Caesar salad recipe, which despite the big talk was bog standard, except for a touch of basil.

Gallagher had come a long way and he knew it. Before Alain Ducasse discovered him in New York, he was just a lad from Donegal, slaving in provincial hotels. Now he was selling his own-brand marmalade and flogging himself on The Late, Late Show. He bought too many of the trappings of success too quick: a Marco Pierre White haircut, a £700,000 Dublin town house and some fancy paintings.

Money troubles started. The hotel that owned his restaurant, the posh Fitzwilliam, bought some of his paintings to bale him out. But then, in 2000, the same paintings went missing from the hotel and the police arrested Gallagher on suspicion of art theft, which he denied. Finally, in March this year, the Fitzwilliam sacked him, claiming he owed the hotel debts totalling more than 80,000 euros.

The Celtic tiger, however, is loath to admit that anything is ever amiss. When we checked in to the Fitzwilliam Hotel last month, we knew none of Gallagher's story and were hoping to eat at Peacock Alley. No one told us that it had shut down until we tried to book a table and the management became evasive. Eventually, an embarrassed receptionist mumbled that the chef "should be in prison", but wouldn't say any more. You can still access the glossy Peacock Alley website and read about all its "very modern" delights. The only sign that anything is wrong is a message that no one has bothered to erase, reading: "Gallagher YOU WANKER."

But despite Gallagher's demise, haute cuisine in Dublin carries on. My second tale concerns the "new star chef of the city". At The Commons Restaurant, underneath the Catholic University building where James Joyce studied, Aiden Byrne cooks up a "meticulously assembled riot of flavours" that is "pricey but worth every penny" (or so says the Time Out guide to Dublin). Pricey is right. A dinner for two, chosen for the cheapest set menu, ended up costing £120 (or 180 euros). As for worth every penny? Well, yes, if you like duck confit shredded in old rancid fat, vinegary lollo rosso, manicured vegetables, logs of uncooked leeks, tasteless sauces, bland cheesecake and service that lectures you on the food before you are allowed to take a mouthful.

This is bad food being kept afloat by a giant bubble of hype and a city full of new cash. Sooner or later, as Conrad Gallagher discovered, the bubble will burst.