It's summertime in Seattle. You have guests visiting from out of town. They love it here! It's so beautiful, with the mountains and the water, and it's not raining at all, possibly because it's the hottest summer ever on record and we're all doomed, but let's not dwell on that. "Let's go to a great seafood place!" they clamor, and you draw a bit of a blank, don't you?
It's not you—Seattle's seafood places, per se, are just not that great. The bigger, long-standing ones, with or without waterfront views, tend to overcook their fish, and tend to get into overelaborate preparations, and tend to fill up anyway, so it doesn't matter that they're not that great.
What you need is a multipronged seafood plan. You should do as much of the following eating as you and your guests have time for—and with any luck, they're paying, because good seafood is pricey, what with the emptying oceans and all. Wherever you go, ask what's freshest and local and in season. Copper River salmon? Arguably worth the steep price. Alaskan halibut? Yes. Local spot prawns? Hell yes! And use the Monterey Bay Aquarium Seafood Watch app (or print out the latest version of the card online), and make every effort to eat only sustainable seafood. Otherwise, you are a bad person.
You should start with sushi. If your guests do not eat sushi and refuse to try, send them home. Otherwise, take them to Shiro's (call and make sure Shiro is working) [UPDATE: As of spring 2014, Shiro is no longer at Shiro's, and the place is, unsurprisingly, reported to not be as good anymore—Eds.] or to Sushi Kappo Tamura (sushi chef Taichi Kitamura trained with the revered Shiro, and he also emphasizes sustainable fish, which are noted on the menu). You might also try Kisaku (a beloved neighborhood place) or Mashiko (a beloved neighborhood place that serves all-sustainable stuff). If you and your guests have lackluster wallets, go to Ten Sushi (a nicer-than-most conveyor-belt place where owner/sushi chef Shinichiro Takahashi uses high-quality ingredients and labels all the fish by country of origin).
While the capital-S Seafood restaurants of Seattle are subpar, newer seafood-centric Westward (with the excellent work of chef Zoi Antonitsas nearly upstaged by the Wes-Anderson-esque, yet unannoying, neo-nautical decor) and the Walrus and the Carpenter (from the marvelous and rightfully famous Renee Erickson) are making absolutely great stuff. The catch: The former only takes a handful of reservations, and zero for the splendid outdoor lakefront seating; the latter takes no reservations at all, and while it has a civilized, wonderful, European-style bar attached to it called Barnacle, which you should eat at as well, that is liable to be full, too. Get there right when they open, and tell your guests we're all sorry about this Seattle anti-reservation situation.
It is important not to overlook fish and chips. Everyone loves the ones at dive-bar classic the Pacific Inn, and the also-unpretentious Pike Street Fish Fry is very good too (and you can eat at Moe Bar next door if you prefer). And as this seafood-eating plan (which is necessarily subject to change) is going to press, there are two new fancy-pants options for fish-'n'-chips: Chippy's (from Ethan Stowell) and the rehabbed Canterbury (reopening soon with 2012 Food & Wine best new chef Cormac Mahoney in charge). These are probably both going to be really good, if you can bring yourself (or your guests!) to pay almost $20 per plate for fried fish and french fries.
If your visitors insist on a waterfront experience beyond Westward, take them to happy hour at Elliott's Oyster House—preferably the outdoor area on the pier for maximal proximity to the sparkling water (more on oysters in a moment). You should also take them on a walk through the glorious Ivar's Salmon House and have a drink in the Whalemaker Lounge—or, better yet, have the drink on the lakeside deck. But be sure to check out the whalemakers—they are real! (If you eat at Ivar's, do not expect greatness.) If your guests insist on going somewhere very fancy, take them to Altura or Canlis. While neither is officially a seafood restaurant, the chefs here—Nathan Lockwood and Jason Franey, respectively—will not do a piece of fish wrong (though now you really hope your guests are treating).
Now that we have broached the subject of oysters, let's discuss the old only-eat-them-raw-in-months-that-have-an-R-in-their-names rule. In summer—especially in the hottest summer ever known to humanity—the icy cold waters where our oysters live get warmer, the oysters spawn (you don't want to eat that), and weird stuff has a higher tendency to grow in the waters (e.g., vibrio, which is what causes the majority of the particularly miserable foodborne illness related to oysters). The R-rule—no raw oysters in May, June, July, and August—is just the common-sense wisdom of the ages. But oyster companies have solved the spawning thing by cooling them down in tanks. As for illness, King County Public Health says that it's July, August, and September—our hottest months—that are the worst for vibrio poisoning from consuming raw oysters by far, "dwarfing the others." Prolonged heat spells make vibrio worse. In the last five years, there have been zero reported cases in December in King County, and 42 in August. But then the wet blankets at Public Health say raw oysters are never safe. In any case, there's lots of other stuff to eat (and drink) at Elliott's, or at the scuffed-up Emmett Watson's Oyster Bar, which is an adorable classic (and an excellent escape from the mayhem of Pike Place Market).
Also recommended, for oysters and other intensely local seafood: Taylor Shellfish Farms' two oyster bars. The good people here aim to "provide you with the freshest oysters, clams, mussels, geoduck, and scallops, brought to Seattle throughout the week directly from our farms," and the farms are close by. The original Taylor on Capitol Hill is smaller and has a retail shop (look for the comically large neon sign with the blue heron on top). You might like this one better for its neighborhood-fish-market feel, but your guests will be more impressed with the new one on Lower Queen Anne—its contemporary silvered-wood-and-steel interior, its huge windows and startlingly close-up Space Needle view. Nautical charts of where what you're eating comes from hang on the walls; the kitchen area has a reassuringly lab-like super-clean quality. I had a dozen Willapa Bay shigoku oysters there last week—these are tumbled in bags by the tide, creating their special deep-cupped shells—and they were briny and sweet and creamy, and expertly shucked with zero bits of shell ($18 at happy hour; $30 otherwise). There's also chilled Dungeness crab (from Oregon at the moment, $24 for a half, served with a pickled-ginger and horseradish slaw that's surprisingly spicy and extremely good), big chilled prawns (from Mexico, alas, at the moment, and maybe the slightest bit overcooked, but with a sinus-clearing cocktail sauce, $12 for four), creamy oyster stew ($9, and much better than the somewhat bland red clam chowder, $6), steamed clams, baked oysters, and more. You should get your guests the geoduck ($12), and not only because it's a local curiosity: It's sliced to order here, and you get delicate little pieces of both belly (richer) and siphon (snappier). It's served smartly with soy sauce and wasabi, though it's really good on its own.
Taylor will be opening another oyster bar in Pioneer Square this summer, so after you've trudged your guests around there... But do not dismiss the component of your own kitchen in your seafood-eating plan. Stop by the Taylor on Capitol Hill and buy some oysters to take home; they'll tell you how to shuck them, and if you're unpracticed and end up bleeding a little, that just makes it more dramatic. Go to the great Mutual Fish or Uwajimaya (if they're not horrible people, your guests should love both), or pick up seafood when you're at Pike Place Market, and cook it yourself. Clams and mussels are very easy—cook in white wine and herbs, serve with white wine and crusty bread. Fish on the grill is great—practice with cheaper fish and no guests, and teach yourself how it feels when you press on it when it's raw, then cooked, then overcooked. Cook it for less time than you think it needs. No, less than that. Pour lots of cold wine, and know that even if you do mess it up, it'll still be better than that big, pricey place on the waterfront.
More info on all the restaurants above is right this way.