The Seafood Restaurant, St Andrews, Fife (01334 479 475). Meal for two: £140

Lunchtime on a sparkling autumn day and I am in a Scottish fishing village which is so perfect it looks as if its construction has been overseen by a film production designer with an acute eye for detail. Old stone, whitewashed buildings crowd in along the curving quayside, and in places the road is strewn with seaweed from when the tide last came in. Because here in St Monans, in the East Neuk of Fife, the place where the land ends and the sea begins feels as if it’s negotiable.

At its heart is a small stone pier and, on it, a blue-painted building, the East Pier Smokehouse, which, I have decided, is the most perfect place in all the world right now. It was launched a few years back by James Robb, an Edinburgh-based contract caterer, to produce various products for retail and for his own purposes. Then two years ago he began opening it for food on the premises. You order downstairs, then take a number and wander up to the simple white-painted dining room in the attic upstairs, with its wood-fired burner. There are views of the crashing waves on both sides and, out back, a terrace for warmer days.

The food is brought up to you in cardboard boxes, though there is a station holding plates and cutlery if you are desperate for such fripperies. There is a whole sea bass, hot-smoked until the skin is the colour of tarnished bronze and the flesh just falling away from its bones, the oils gently running. It is a sometimes bland fish turned into something rich and hefty and regal, all for £12.50. Their own sweet-sour chutney with the crack and burst of whole pink peppercorns closes the deal. There is fresh local lobster – £17.50 per beast – with chips made by someone who cares, and a pungent smoked fish curry full of haddock and mussels and attitude. Even the basmati rice on the other side of the box is cooked precisely.

I run downstairs, to babble enthusiasm and delight and to check on opening times. “Oh, this is the last weekend,” I’m told. Sorry? “Yup. After tomorrow we’re closed until Easter 2016.” I am a crap restaurant critic. Useless. A waste of space. I am telling you about a brilliant place you can’t visit until next year. Shame on me. But I’m doing so partly because you need to know about it, and partly because it puts in stark relief what happened next.

I had a booking at the Seafood Restaurant in St Andrews, made under my own name as I didn’t think I’d be reviewing. But hell, what use are my reviews if the places aren’t open? I would write about that instead. It occupies a modernist Bond-villain glass box perched on a bluff overlooking the shore in the buffed and polished town and has something of a reputation, which the quality of two main courses almost justify. But if ever there was a restaurant which proves that a couple of good dishes do not a night out make, it is this one.

As a university, St Andrews has a reputation for attracting the very well-heeled crowd and on a Saturday night, here they all are. In the middle of the bare, hard-surfaced dining room is a table of young people who may or may not be students, one dressed as some sort of medieval knight complete with metal sword, presumably because that sort of thing is hilarious. They bray and slump and lounge about the table. Most of the rest here seem to be students with glossy hair trying not to scowl at their parents in case their allowances get docked. Forgive this lurch into class-war sneering, but these are restaurant reviews, not just food reviews – and the other clientele matter. It is a grim place full of hauteur and lip curl. (Of course, they may well have disliked the look of me. Each to their own. They are clearly not mine. I am not theirs.)

But this clientele appears to have a major impact on pricing. Two courses are £40, and three £50, for cooking which has lows so very much deeper than any highs. They are the sort of lows weather forecasters point to on maps of the Atlantic, with something approaching awe and respect. Snacks are a cold, tired choux-pastry ball dribbled with sticky balsamic vinegar and a stone-cold “dough ball”, a lump of dense bread that has seized up and will never show signs of life again. They both taste of the words “Will this do?” No, it really won’t.

The waiter gives us a breathy spiel about the quality of the fish that came in today for the sashimi plate and how the chef is thrilled by it. Well, if the chef is thrilled I must get in there. The Japanese embassy might now like to instruct its lawyers to sue for defamation of an entire culinary tradition. It doesn’t matter what the quality of the fish is if the knifework is as clumsy and blunt as here. These aren’t slices of fish. They are bricks, served far too cold, and on a bloody slate. There is a thick soy dipping sauce. It tastes of salt and treacle with heavy back notes of paraffin. It is unremittingly foul. A crab velouté is a massive whack of salt. It remains only half eaten by my companion. Naturally enough I find myself dreaming of a smokehouse by the shore where the food comes in cardboard boxes. The comparison is stark and brutal.

And then we get those main courses, which go some way towards explaining the restaurant’s reputation: a whole trimmed lemon sole, accurately cooked with a sultry puddle of brown butter and nutty brown shrimps, the flesh slipping gently from the bone, alongside samphire and spinach; a fillet of stone bass, again accurately cooked, on a heap of potatoes mixed through with generous flakes of smoked haddock. It is very hard to understand how a kitchen which can produce food of this quality can also be responsible for the dismal snacks and starters.

We share just one dessert, a banana cheesecake, and it’s fine. But I cannot see how it justifies the £10 price tag that comes with moving from two courses to three. I anaesthetise myself with expensive glasses of Albariño and brood on the fact that really, with restaurants like this, it doesn’t matter what the hell I say. They have their audience. This leaky ship will sail on regardless.

■ Hix Oyster and Fish House in Lyme Regis is another architecturally distinctive seafood restaurant, albeit one that’s more reliable. Go for whole crab, barbecued huss with coleslaw, fish curries, and a killer snack menu including the genius that is crispy Atlantic prawn shells: the most compelling prawn crackers ever (hixoysterandfishhouse.co.uk).

■ Condolences to the Sánchez-Iglesias family, and the team behind Casamia, on the death from cancer of chef Jonray Sánchez-Iglesias. With his chef brother Peter he took the small Bristol restaurant to extraordinary heights. The Sunday Times-Hardens list of Britain’s top 100 restaurants recently put Casamia at number 4. Jonray was just 32. He leaves a wife and two children.

■ A quick Ding Dong Merrily on High for the re-publication of Josceline Dimbleby’s classic Cooking for Christmas, which includes the greatest mince pie recipe ever. They’re made every year in my house – though, as my wife points out, not by me (clearviewbooks.com).

Email Jay at jay.rayner@observer.co.uk

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