Sharkbait & Swim, Arch 11, 4 Deptford Market Yard, London SE8 4BX (info@sharkbaitandswim.com for bookings). Small and large plates £4.50-£22, wine from £26

Oyster lovers travel hopefully. It’s not that we think we’ll always be the ones to dodge the “bad” oyster. We don’t fret about the bad oyster at all. That’s a paranoia for oyster agnostics, for the ones who think they ought to like them, but will quietly admit they are suspicious of the proposition. Our hope is that we’ll encounter not just the good oyster, but the better oyster and perhaps even the very best, for not all oysters are made equal. Some deliver that invigorating hit of saline and briskness, but lack body. Others are more substantial, but a touch one-note.

And then there are oysters like those served to me at Sharkbait & Swim, a restless, mildly eccentric seafood restaurant in the Deptford Market Yard development by Deptford overground station in southeast London. They are rocks, of course, for there is currently no R in the month and the natives are out of season. That doesn’t make them second-class citizens. These rocks are plump and pert. Along with the slap of brine and roaring surf comes a profound creaminess and sea urchin funk. My reference point for these is the superb pearly specimens I have eaten at the Acme Oyster House in New Orleans, where men with forearms like hams keep them coming across the bar all night, with only Tabasco for company. That is high praise indeed.

Here they cost £2.80 each, or £15 for six, a good price for anywhere within the M25, and most places outside it for that matter. They arrive with a plastic aerosol of whisky, which we are invited to spritz over the top, followed by a squeeze of lemon. I am not sure about the whisky thing; it feels like an affectation – until I try it and begin to wonder whether a dab behind the ears wouldn’t go amiss, too. It would surely attract all the right people. The oyster is lent the airiest touch of sweetness, which is then saved from itself by the squirt of lemon.

For £3.20 each you can also have them haute couture-dressed: with the citrus burst of, say, ponzu, ginger and coriander, or the seafood-enhancing Thai fish sauce-wonder that is nam jim jaew. These oysters are more than capable of holding their own and, indeed, being helped along by these big flavours. It’s a serious opener. After dinner, as dusk falls, chef owner Steve McClarty tells us the oysters are Colchesters, which adds a sweet historical resonance. In the 19th century, at the height of London’s dizzying oyster cult, barges full of them would steam down from Colchester, turn right at Southend and go up the Thames estuary to deliver their cargo to an eager city. Our slightly rickety chairs out here on the cobbled yard are only a few hundred metres from the Thames. It is the kind of historical resonance, the whispers and echoes of the past, that old cities are so good at.

Sharkbait & Swim occupies a red-brick railway arch amid a clutch of restaurants, including an izakaya and a jerk place. There’s an open kitchen in the arch that, in winter, can seat around 20 at high-top tables, as long as diners don’t mind a bit of armpit and elbow intimacy. As a result, they depend on summer, when seating outside means they can double their covers. Certainly, the current menu is tailored to the warmer season. The list of small plates, mostly priced at between £10 and £12, feels very now. Fat cubes of trout ceviche arrive in a dazzling piece of blue glazed ceramic, swimming in a chilled, heady broth of yuzu and soy. For texture, there are big puffed grains of rice, like larvae. There are lightly bitter deep purple leaves and a scattering of peppery spice.

Big, oily fillets of mackerel have been grilled until the skin is blackened and blistered. There is a sweet tomato and butter sauce and the bosky green of herb oil. Deep-fried whitebait, and sizeable specimens at that, have a chilli-boosted golden crumb of such rough heft, you can hear them rub against each other when you shake the plate. There is a pot of soft-peaked garlic aioli on the side, to lubricate everything. The most expensive dish, at £22, is a whole sea bream, lightly battered and deep fried, so it’s starting to curl in on itself, then pelted with what seems to be togarashi spice. This corner of southeast London has a fine collection of very good Vietnamese restaurants, where whole fish treated like this is a part of the deal. They don’t, however, generally come with a pile of chips underneath. Ah, hello carbs my old friend. We could do with a bit of that right now. We pull at the fish with our grease-slicked fingers, as if we’re excavating.

The special tonight is ox cheek and miso croquettes, with a softly warming jalapeño jam. They look terrific: round, sturdy and golden. They also win on big meaty and umami flavours. But something has gone a little awry with the bechamel. When I cut in, the filling flows out across the plate like the plumbing has failed. I give thanks that I didn’t just pick one up with my fingers and bite in, or I’d probably be combing oxtail goo out of my beard to this day. I’m aware this is not an image anybody needs. There is no sweet offering save a mercifully short “dessert booze” list, including limoncello, the Toilet Duck of the booze world, and various milk and dark chocolate liqueurs, which might seem like a good idea at the time and really aren’t. The wine list is perfunctory, but they’ll mix you a sticky cocktail. Service, by just one person juggling tables, is on point.

Deptford right now is feeling the hot, steamy flush of new money. Older businesses remain, but you’re also never far away from a bar eager to sell you a natural wine smelling of arse or a coffee that’s a classy tribute to carbonic maceration. Some might now be moved to sing the gloomy ballad of gentrification. Before you hit the chorus, let alone the second verse, know this. Steve McClarty has worked as a chef for Google and alongside Jason Atherton on television. But when he was 17, he was homeless. He kept himself going in hostels by watching YouTube cooking videos, then cooking for his fellow residents. Eventually, he enrolled himself in catering college. Which brought him here. If you begrudge him this delightful small restaurant, perhaps you’re really not quite as enlightened as you think you are.

News bites

Just published: the debut cookbook from the Syrian chef and restaurateur Imad Alarnab, who fled Damascus for London during the civil war, arriving in London in 2015 where eventually he was joined by his family. He went on to open his rapturously received restaurant Imad’s Syrian Kitchen. The book, which has the same name, is subtitled ‘A Love Letter from Damascus to London’ and shares recipes from the restaurant, alongside the story of Alarnab’s journey to the UK and of Syria itself.

I am very much divided on this one. On the one hand I am dismayed to learn that the owners of Simpson’s in the Strand, which never reopened after lockdown, have decided to sell off all of its fixtures and fittings, from its beautiful art deco mirrors to stacks of Wedgwood plates; from the red leather chairs to battered metal trays from the kitchens. This includes the famed roast carving trolleys. It is the dispersal of a truly extraordinary heritage. On the other hand, as it’s happening, I’ve signed up to bid. The viewing is 1 August and the sale is on 2 and 3 August. You can register here.

And Jeremy King, co-founder of the Wolseley, Delaunay and Zedel among others, has announced a new venture. King, who was forced out of the company last year, will open The Park in a newly developed ground floor space at the corner of London’s Bayswater Road and Queensway next spring. He says it will be a modern version of the grand café and brasserie for which he is renowned.

Email Jay at jay.rayner@observer.co.uk or follow him on Twitter @jayrayner1