Zucca introduces itself as an ­"artisan Italian restaurant, located in the west end of Edinburgh's theatre district, a firm favourite with the pre-theatre crowds, tourists and locals alike looking for great food without too much fuss and formality".

That description causes me to ­stumble. Zucca's location does position it on the fringes of the capital's West End, but the west end of its "theatre district"? Steady on. New York and Paris have theatre districts, but Edinburgh? I'm not convinced.

All the thespian action of late has been at the Festival Theatre - most definitely not in the city's West End - where the National Theatre's rendition of Michael Morpurgo's War Horse has been packing them in, with barely a dry eye in the house by the second half. I know this because pre-theatre crowds have been flocking into Spoon, just across the road, which is one of my favourite lunchtime spots. Fortunately, this endearingly fresh and indie eating place has a loyal, well-established clientele, so it does not rely on the fickleness of arts events for custom.

At Zucca, however, I have never come across a room full of diners so homogenous in their demographic. The Lyceum next door - Zucca is practically that theatre's canteen - was staging Noel Coward's Private Lives, possibly not the edgiest of plays, the night I visited. Judging by Zucca's clientele, who made a mass exodus by 7.30pm, Coward attracts the sort of viewer who would be watching re-runs of Midsomer Murders on ITV3 of an afternoon.

I'm one to talk. For me, Midsomer is ­irritatingly stereotyped and twee, but I'm a sucker for Columbo. Peter Falk's "Just one more thing, sir" line really cracks me up. But put it this way, on the night we visited, Zucca was not playing to a rock 'n' roll audience.

Zucca's menu is tuned to the middle-of-the-road, Classic FM constituency it seems to cultivate. It says that it "aims to offer elegant but simple food, using fine Italian and Scottish produce, reflecting both seasonality and the chefs' creativity, maintaining a Mediterranean theme throughout", but for me that was just a load of old cliché.

I saw absolutely no evidence of seasonal awareness - quite the opposite actually, with the usual tired line-up of supposedly southern European food (aubergine, basil, green beans, cherry tomatoes), typically provided courtesy of Dutch, Spanish, Kenyan and Israeli growers. Isn't it time that restaurateurs stopped torturing the much-abused word "Mediterranean"?

The menu is dull and derivative, but perhaps that's what Zucca's patrons like. Theoretically, you can eat two or three courses here for £14.95 or £17.95 respectively - if, that is, you ignore all the supplements noted on the menu: roasted tuna salad (£2), beef carpaccio (£3), steak (£6), scallops (£3) and seabass (£3). The latter is not described as line-caught, so it seems fair to infer that it is farmed, and thus both abundant and competitively priced; in which case, no supplement is justified.

These add-ons up the bill by stealth, although if you are a vigilant member of the thrifty Which?-reading middle classes, savvy menu choices will allow you to cut your cloth to suit your income.

Our food was not only dull, it was also poor. Neither the ingredients nor the cooking had much going for them. Some dishes, such as the solid, over-processed duck terrine with its see-if-you-can-spot-them pistachios, were fridge-cold.

Arancini had a fishy-smelling greasy breadcrumb coating, similar to what you get in poor processed food, and cracked open to reveal mushy, under-seasoned rice stodge minus any obvious presence of the advertised smoked mozzarella.

The bass, with its flaccid, adhesive, uncrisp skin and nondescript taste was noticeably unseasoned; it has put me off this species for a while. It came with watery sweet spuds and what tasted like single cream mixed with pesto from a jar. The rib eye steak was disastrous, as if it had been grilled directly on charcoal doused with lighter fluid. Slimy mushroom and turgid hot tomato added to its inedibility.

Desserts come from rows laid out under cling film in a fridge. Miserly quantities, crammed into latte glasses. Chocolate mousse concealed unroasted hazelnuts bulging out of their moisture-logged skins. Maple banana cheesecake was very little apart from whipped cream.

A poor show all round.