20 St John Maddermarket,
Norwich NR2 1DN
01603 449781
Meal for two, including wine and service £90

This week's restaurant is housed in what, from the outside, is a lovely hunk of oldness. I want to say Victorian, but perhaps it's Georgian. Or older. Or younger. I don't know. It's pretty. What do I know about architecture? And the mere fact that I am banging on about the outside of the restaurant, as if standing with my toe on the threshold, hesitating before taking you inside, speaks volumes. Can I also say that the people inside seem nice? Smiley. Rather sweet. Welcoming. Oh God.

This is tough. Not as tough as it's going to be for them to read, but less than easy all the same. I considered reviewing without naming them; holding up the faults at 20 St John's as ones from which others could learn. But that, I realised, was a stupid idea. They may be nice people. They may have their hearts in the right place. But they are still charging money – £90 for two is not peanuts – and, after all, who am I writing for?

So come with me then, into the flag-stoned hallway, which is brightly lit. Not just "Oh, I can see my way" brightly lit but "Blimey, that's a bit sharp" brightly lit. And from there into the "lounge", which is the last place you'd want to do such a thing. The lights are up so high you can see every scuff mark on the walls, every tatty seam on the oddly positioned dun-coloured sofas. Young people's music clatters and bangs off every hard surface.

We order a couple of "Kia Royals", which I assume is a misprint of "kir" until I taste it. It's viciously sweet. I wonder, cruelly, whether the name is correct and it has indeed been made with Kia-Ora. Then I think: maybe it's my fault. When what should be a mix of champagne and a blush of cassis costs £4 the clue is in the price. One of the staff gets out a mop and starts slopping down the floor in the doorway. Through to the completely empty dining room, which is equally brightly lit. The music continues to rattle the lonely glassware. This is a very quiet restaurant. It is trying. To which I immediately want to add "very". It feels like a place that hasn't worked out how to do the thing it wants to do.

The food is a mix of odd and uncertain and not quite. Sautéed field mushrooms come on what feel like toasted pieces of pre-sliced brown bread. The advertised smoked stilton – why would you smoke stilton? – makes no impact. It's a pile of things, as though cobbled together from ingredients at the back of the fridge. Dense cod fritters come on a big, dry pile of garden peas with hunks of chorizo. There is meant to be a butter and sage sauce, but there is no sign of it. A main-course duck dish is brown. Very, very brown: a few squares of roasted brown root vegetables, a huge brown breaded mashed potato croquette like a draught excluder, some slices of overdone brown duck. A brown sauce. It's a strange plateful for £17.50. Better are some plaice fillets with planks of crisp bacon and vast amounts of mash. We console ourselves with a well-priced bottle of St Emilion.

Desserts are the one clear success. A crème brûlée with Kahlua is a bit solid, but at least you can't taste the Kahlua. A pear and almond tart is an expert piece of tart making. Pastry seems to be something the kitchen is good at. From time to time someone wanders into the dining room to ask if everything is all right, but we don't want to intrude on private grief by being honest so we say fine.

This restaurant was chosen for review after much research. Views were sourced, temperatures taken. The website looked convincing. I did not want to go to the obvious places. It was with the best of intentions. The team here have a lovely site, they really do. But if they want it to work, they have to change. And they could start by turning down the lights, before somebody else comes along and switches them off altogether.

Email Jay at jay.rayner@observer.co.uk or visit theguardian.com/profile/jayrayner for all his reviews in one place