It’s too hot to write a long intro, I don’t have the strength, so let’s just get straight into the restaurant. In the restaurant, it’s cooooool. The aircon is on full, like I’d dreamt it would be, ducking out of the back of the stifling minicab – a brown Vauxhall, ancient, diesel-powered, fuzzy polyester seats, air temperature on this hottest day of the summer getting into the low nineties – because the traffic in Gower Street was jammed solid, tyres welding themselves to the tarmac, and bolting into Euston Square Tube to take the underground to Piccadilly, which would be out of the sun, and considerably quicker.

Or would have been if Euston Square had been on the Piccadilly line, like I’d thought. But that’s Russell Square (damn squares, everywhere, like we’re supposed to know the difference), so I had to change at Baker Street, march the length of a sun-baked outside platform, and then suffer the dust and swirling particulates of Piccadilly Circus and be held, broiling, on the central island (under Eros) by endless bendy buses, the kerbside press of sweating tourists growing thicker and thicker…

Then finally the shaded scuttle up Glasshouse and into the sun of Brewer Street – please let it be high-ceilinged and breezy, please let there be aircon – looking for number 66. But it isn’t there, backwards and forwards I go, roasting in the glare, phoning 118118, where they know nothing, nothing, not even their own names, and then 118500 to get the number to call Aaya to ask where the hell they think they are, steaming, poaching in my skin, and then looking round and realising that I am there, after all, but it’s just a name carved into the yellow stone, discreet and unexpected, so I kept missing it.

There’s a little reception desk at the door, with a little receptionist standing at it, and to her right, my left, the dining room is, thank God, high-ceilinged, breezy, and the aircon’s on full. And it’s cooooool, inside, and the damp on the back of my neck begins to chill, and I find room for a cold Japanese lager and a bottle of sparkling Belu.

The ceilings are high, and the bar is long and racked with bottles – downstairs there is another dining room, bigger but lower-ceilinged, equally sleek, with the longest sushi bar I’ve ever seen, which I only discovered later en route to the loos – and the tables are nicely spaced with plump chairs and banquettes and a plasticcy, Sixties vibe that I like. No airs and graces. That can bode well with a new Japanese joint, or it can bode badly. “Bode” is a funny looking word, isn’t it?

The place is owned, I gather, by Gary Yau, brother of Alan, whose latest venture, Cha Cha Moon (reviewed here the other week) was a good example of a place where having no airs and graces boded (bade?) extremely badly, for the food was execrable. Indeed, Cha Cha Moon had plenty – as Winston Churchill might have said – to have no airs and graces about. But then again, big Al also has Hakkasan and Yauatcha, which have airs and graces by the bucket-load, and are exceptional.

It is a good menu. There is a lovely wide range of sashimi and sushi (easily 20 of each) which lets you know where the soul of the place lies (outside Japan you cannot get away with serving just raw fish, and we must accept that), and then a nice, modest array of grilled and braised things and a dozen or so cold and hot dishes of a style one might call “post-Nobu”, which is to say sort of basically Japanese but dicked about with to quite satisfying effect.

From this last genre we had three grilled kumamoto oysters (a unique Japanese breed, rather small and muscular, that is very popular in West Coast American sushi restaurants) with ponzu sauce, which actually weren’t grilled at all. I notice now, looking at the menu, that not-grilled kumamoto oysters with ponzu sauce are also available, so I guess that’s what we got. They were fine. But then we also had king crab with ponzu jelly that were quite lovely: sweet white crab meat on lengths of leg shell with a sweet-meaty golden aspic that brought new life to a familiar flavour, a change from lemon, lime, mayonnaise, all the usual crab stuff.

Then a round of sashimi which was delayed as the chef cut into a new yellowtail. We ordered, and got, two pieces each of chu toro and o-toro. Both are fatty tuna, but the o-toro comes from a little further forward on the belly (stop me if you know this) and is that bit fattier and that bit sweeter and thus a tad more expensive (£4.50 here for two pieces, as opposed to £4). Both were very good, leaving that telltale oily slick on the surface of the just-skimmed little bowl of soy that you never get from plain old maguro (the red, dorsal tuna you get in Yo! and Hi! and all the other joints with exclamation marks).

The yellowtail (hamachi) was decent, too, but the scallops, which I love above all sashimi, were a little off-key. They didn’t have quite the zip and sweetness that makes them, at their best, almost fruit-like, and that was because, I think, the sashimi arrived a couple of degrees above ideal temperature (a bit like me), which is not a problem for the finny stuff, but for the scallops was perhaps a bit of a challenge. A tiny quibble, though. First-rate sashimi.

We had a couple of maki rolls, very good inside-out spicy tuna, with the fat of the fish and a real whiz of chilli helping me get over my ancient Taoist snobberies about new sushi. And the dragon roll, bound in shaved avocado and topped delicately with three salmon eggs (ikura) was spot on as well.

What else? (It’s funny, this thing with not doing an intro and just writing about the food – you run out of things to say.) Oh yes, the hot food. The mixed tempura, four prawns – and then bits of okra, wild mushroom, shiso leaf, other things – was excellent for £9, and it was lovely not to see the same boring old vegetables. Beef toban yaki arrived sizzling – woohoo! – and was not bad at all.

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