KING STREET BLUES -- 112 N. St. Asaph St., Alexandria. 703-836-8800. Open: Monday through Thursday 11:30 a.m. to 10 p.m., Friday 11:30 a.m. to 10:30 p.m., Saturday noon to 10:30 p.m., Sunday 3 to 9 p.m. MC, V. No reservations. Separate non-smoking section. Prices: appetizers $3.25 to $5.50, entrees $4.50 to $9.75. Full dinner with beer, tax and tip about $15 to $20 per person.

THE MUSIC MAKES YOU WANT TO get up and do the Hucklebuck, the menu makes you want to live on fried onion rings and mashed potatoes. And for those of us who grew up on real old-fashioned rock-and-roll, King Street Blues may not be good for the heart but it is balm for the soul.

This is a three-story neon-decorated roadhouse that plays and cooks the classics of the '50s and '60s. It does everything with a giddy twist, from painting the staircase suede-shoe blue to hanging serious picture frames with whimsical portraits of burgers and subs. The first floor is a bar, the second floor and balcony above are dining rooms. With murals meandering up the walls and cartoon animals frolicking on the balcony railing, this is homage to the casual, the homey. Sure, it's noisy; but even so, you can talk. And to be honest, the chairs are pretty flimsy and uncomfortable, but you can opt for a wooden booth if you intend to stay long. For a roadhouse there is a surprisingly small selection of beers -- only four -- but they include a yeasty golden Virginia Native Brite made by the new Old Dominion Brewery.

King Street Blues is the new home of chef Michael Soper, formerly of Union Street Public House, and the menu shows his style. There are po'boys and barbecue, old-fashioned stews and platters of meatloaf and country fried steak. A Cajun touch sneaks in here, a Deep South accent there. And this is definitely a place to save room for dessert, particularly if your mom no longer makes apple cobbler.

But King Street Blues means to be more than a restaurant -- it's sort of a three-story neighborhood. The menu lists all the principal players in the business, and it chats with you, reminding you to sit up straight and eat your vegetables. Cartoon characters peek from among the platter and sandwich listings, just as they populate the mural that sweeps up the staircase.

So the menu is friendly, the walls are friendly, the prices are friendly, the serving staff is friendly. It's a happy place, but with one nagging problem. The food is not yet up to snuff. At least not up to Soper's usual snuff.

You can have a terrific meal at King Street Blues, but you've got to have a road map to do so. You could start with griddled corn fritters and Virginia ham, and if you don't mind that these thick corn pancakes are a little gummy, you'll cheer for the combination and probably recommend them to your friends. If you like fried stuff, you'll revel in the thin, spicy, crunchy fried onion tangle (though sometimes it is too salty), and you'll check your calendar to see when you can return for another fried catfish sandwich. It's the sweetest, juiciest catfish you'll ever find sealed in a crunchy cornmeal coating. And I've seen meatloaf snobs finally admit that somebody besides themselves could make good meatloaf once they tasted the thickly sliced, gently bready and onion-spiked meatloaf Soper serves under a blanket of sweet-sour warm onion relish. Sharing the plate are creamy, buttery garlic mashed potatoes that are worth ordering on their own (though the kitchen has been known to turn them gummy on occasion).

The flaws have been hard to anticipate. With such an original, eccentric and spicy pork chili with white beans, and rich, creamy pine-bark stew of seafood and ham in a boldly spiced base, why is the chicken and oyster pie so thin and bland? When the onion rings are likely to be oversalted, why are so many other dishes -- from the ribs to the chicken pie -- devoid of salt? With such nifty mashed potatoes, why is the potato salad not only tasteless but also cold and stiff? It tastes as if it had been forgotten in the back of the refrigerator. And why are the barbecued and grilled meats so dry and faded? The St. Louis Ribs are almost wonderful, having been rubbed with dry spices and smoked to a dark, crusty finish. But besides needing salt, they have a greasy soft texture that suggests reheating. Spiced chicken legs -- called Hot Legs -- also taste reheated, dry and faded. Grilled sliced sirloin is teamed with excellent fried oysters for a Montana's Big Boy sandwich, but the beautifully charred yet leathery meat tastes like wall decoration, not sandwich makings. And pork barbecue, whether sliced or chopped, has all the above flaws and more; its problems seem terminal. Even on one plate, the food is uneven. A Low Country Saute of chicken, shrimp and andouille sausage is an invigorating array of meat, with stellar chicken and shrimp but oddly knackwurst-like sausage. And the accompanying red rice tastes like what my elementary school cafeteria served to make us beg our moms to let us come home for lunch.

Fortunately, among all the menu's dicta, none warns that you've got to finish your meal before you can get dessert. Desserts are good enough that they might even force me to swallow the red rice. The cobbler, made of different fruits on different days, is just plain lovable. Apple, for instance, is tart as well as sweet, drenched in cinnamon and topped with an irresistible thick, buttery, tender and crusty layer of dough that tastes like biscuits married to cake. Deep Trouble Chocolate Cake also tastes like a happy marriage -- of brownies and fudge. And Cool Lemon Pie is like key lime pie -- condensed milk, crumb crust -- but with honest lemons rather than fake key limes.

King Street Blues needs to improve the harmony of its cooking. Even so, its kitchen already plays enough sweet music that, as the menu advises, you can "Eat well and remember."