The seafood case is the first thing you come upon when you walk into BlackSalt Restaurant and Fish Market, the goods glistening atop slabs of granite—ropy, veiny filets of monkfish bundled like kindling; a corrugated fan of skate wing, that hard-to-find delicacy of the deep; octopus tentacles so smooth and slimy you half-expect to see them wriggling from their perch and making a break for it.

The kitchen does not renege on the market’s promise—the seafood is uniformly firm, supple, clean, and fresh. Pop the oyster crusted in masa harina into your mouth: That seawatery bite is exactly what you hope you’re getting for your three bucks. Or dredge up some of those sweet, meaty hunks of red snapper in the teeming “zarzuela” stew: I dare you to find better, more flavorful snapper anywhere in the city.

So why have I left every one of my four meals here wondering, What if…?

It’s not for lack of trying. BlackSalt is Jeff and Barbara Black’s fourth restaurant and their most interesting by far. I was prepared to revisit the highly successful formula of Black’s Bar & Kitchen and Addie’s, especially after watching the couple crib from themselves this past fall in opening Black Market Bistro in Garrett Park—like its predecessors, a casual place where the menu looks to comfort rather than challenge and fish predominates.

But BlackSalt isn’t another spinoff; nor is it the cunning, punning remake of the original I supposed when I first heard the name—Black’s Alt? Instead, it appears as though the veteran restaurateurs, emboldened by their string of successes, have decided to take a chance and extend themselves. The design scheme transforms the fish market into a set piece of industrial chic, while the menu flaunts its range: five kinds of mussels, three fish stews, a chowder or two, a selection of oysters, a number of daintily portioned plates of crudo, plus a half-dozen preparations of the catches of the day.

No, the fish never smells, but the place reeks, nevertheless—of ambition. The evidence is everywhere that, with this venture, the Blacks are bidding to rival Jeff’s old mentor, Bob Kinkead, as the city’s premier purveyors of quality seafood. The fried Ipswich clams, a near-duplicate of the definitive version offered at Kinkead’s, amount to a wink-wink acknowledgment of those intentions. And the ritual by which every plate of oysters is brought before the chef for inspection before going out to the customer—a tiny detail, perhaps, but one that guarantees their being always cold, clean, and impeccably shucked—is a pointed reminder that in the restaurant business, a lesson copied is a lesson learned.

Still, something of the middlebrow caution of BlackSalt’s sisters clings to the place. The more I venture beyond the small plates and the oysters and the mussels (particularly a terrific Moroccan-style preparation, with preserved lemon, tomato, and merguez), the more I’m reminded of the can’t-leave-well-enough-alone tendencies of an overproduced Hollywood movie—the kind that doubts a scene of simple power and so bathes it in sypupy strings.

An insistent busyness runs through many of these plates. A log of tuna is inexplicably turned into a loin of pork, dusted in chopped, weedy herbs and paired with a goopy mushroom risotto and a tangle of Swiss chard; the presumed counterbalance, a fennel-citrus relish, isn’t strong enough to make itself heard. A sweet filet of dorado, or mahi mahi, is gilded not once, not twice, but three times: first with an exceptionally creamy polenta, then with some soft, blistered tomatoes, as if more sweetness were needed, and finally with a rosemary-butter sauce. Monkfish arrives atop a layered cake of potatoes Anna, the whole thing blitzed with a sauce of vinegar and pancetta. It doesn’t take long for the sauce to penetrate the delicate layers of potato. You come away from the dish remembering not the gorgeous fish, but the sodden cake and the peppery, bacony tang.

I find myself wishing the kitchen would trust more often in the unimpeachable quality of its fish. If it can pull off a braised baby octopus as good as it does—the critters, dressed in garlic, tomato, and red chili, have the purity of sashimi—you’d think it could rein itself in elsewhere. A clam-and-oyster stew is studded with plump, juicy goodies, but it’s as if someone in the back were intent on a cover-up, given the heavy-handed use of cream, bacon, and herbs; a tomato-based bean soup, with its hunk of salty cured tuna and strip of pecorino, is a cacophony of intentions. If a Portuguese fish chowder succeeds, it’s because the broth, laced with chorizo and kale, supports, rather than obscures, the sweet, briny flavors of the fish.

The kitchen might want to pay more attention to the deft handiwork of pastry chef Susan Wallace. I’ve tried every one of her desserts, and there’s not a dud in the bunch. To read the menu is to brace yourself for the dully conventional—tiramisu, crème brûlée, chocolate peanut-butter cake, bread pudding, cookies—but they’re rendered with such skill and delicacy that Wallace injects new life into the tired and familiar.

She also brings you full circle. You end where you began when you first walked through the door: dazzled by the sheer, reductive power of simplicity and willing to believe in the promise of this young and ambitious restaurant.

BlackSalt Restaurant and Fish Market, 4883 MacArthur Blvd. NW, (202) 342-9101.

—Todd Kliman

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