Those who bemoan the devastation of our pub heritage by bars and gastro-whatevers should have little cause to mourn The Penny Black.

Formerly a bit of a blight on the ever-increasing grooviness of Exmouth Market, there'll be few to lament its demised skankiness, except possibly a couple of disenfranchised post office workers from the neighbouring Mount Pleasant branch.

Anyway, where once there was grunge, there's now glitz and glitter. Las Vegas-style glitter, to be precise. This is $. How very postmodern, how very terse, how very tedious. Even giving it its full moniker - $ Grills and Martinis - doesn't make it any less of a piece of onanistic posturing. I suppose it's intended to appeal to the designer-spectacled types who infest this part of the world; on a drizzly January evening it had spectacularly failed to hit its target audience.

The date, normally reluctant to relinquish the prized looking-out-ontothe-room table, was quite happy to watch the goings-on in the street rather than catch the non-buzz on the floor. Apart from a brace of urbane restaurant-addict brothers of our acquaintance who hit every new opening almost as a matter of honour, we're talking smallmoustacheand-Next-suit dull.

Downstairs, there's a dimly-lit bar, all alcoves and windowless gloom. Like Vegas itself, it's the kind of place where time loses meaning and hours disappear into the bottom of martini glasses. On the first floor - the restaurant - murals referencing the Nevada fleshpot provide focal points alongside gorgeous, fireworky light fittings and zinctopped tables. It looks good: shame the punters didn't do it justice.

Neither did the food. $'s menu is not a highly evolved one. We didn't really expect great things from the worryingly thin chef in his tiny open kitchen. And the choice - which included club sandwiches, burgers, Caesar salads, even a sighting of the dreaded sun-dried tomato - didn't exactly pulse with promise. But you can still execute basic stuff with aplomb if you set your mind to it.

A good prawn cocktail, for instance, is a lovely thing if the ingredients and assembly are right. Here, an American-style version (ie not mayonnaise-based) came with shrivelled shrimp, limp lettuce and a lurid sauce that tasted of Bick's Hamburger Relish. A salad came doused in too much strident balsamic which meant that, even if I'd managed to locate much of its alleged lobster content, I'd have been unable to taste it. And orange slices? With lobster?

Main courses weren't much cop, either. A hamburger was dry; perhaps to compensate it came with a dish full of little pickled onions. This was just too camp (like our waiter, who called us 'my darlings' throughout the meal and couldn't have been more charming). Bouncy prawns and mangled bok choi came with a kind of rice pudding doused in coconut milk and chilli. So that, and only that, was what I tasted.

'Would you like one of my puddings?' trilled our waiter. Glad we did: a little, highcrusted pecan and caramel pie proved the star of the show - gooey and nutty with a really well-executed shortbready pastry. So they can pull it off, occasionally.

To be fair, $ (try getting that number from one-one-hate) is not really a restaurant proper, or even a gastropub, it's a diner, with shallow diner ambitions and prices - three courses for two with wine comes in at around £75, although hit the rather good martinis and you could still head for a pretty painful bill. And if you're looking for an eye-candy, stomachlining pitstop before a North London bar crawl, you could do worse. But, with the likes of Moro just a few steps down, you could do a whole lot better, too.