The first thing you notice about Rockfish is the tin washtub of peanuts near the entrance with a sign inviting diners to grab a tin bucket and fill up. The second thing you'll notice is that the floor crunches as you walk to your table--if there is one. Most likely during lunch and dinner hours, when it's packed, you'll have to take a seat at the bar, stand around the counter area, or loiter outside and toss your spent peanut shells in the grill of the new Lincoln parked in front.

Which is appropriate, because just as people need to let their hair down every once in a while, haughty cars need to get down to the level of a duct-taped Chevy Cavalier.

And this is the kind of casualness Rockfish facilitates. It's a clean platform conducive to the elegant slob in all of us--or inelegant slob if you have too many frozen margaritas, which is easy to do, as those peanuts generate an awful thirst.

The newest creation by See-Worthy Restaurants, the folks that gave us Shell's Oyster Bar and Grill, Rockfish is stuffed in a strip mall on Park Boulevard in Plano in the former ZuZu location. It's rustic in an L.L. Bean sort of way: rugged with a keen eye to fashion consciousness. An open kitchen and thick layers of lacquer distinguish Rockfish from its Shell's siblings. The sheen stretches across hardwood floors, wood tables, and step-up pine booths.

But Rockfish still incorporates some of the same quirky garb that bedecks Shell's, such as inverted tin bucket chandeliers and walls holding fish trophies and fishing pictures with goofy captions. The back bar is a roughened windowpane framing a recessed beach scene applied to the wall behind it, spicing your visit with that jarring Viewmaster perspective before you've even had your first margarita. Above the front counter hangs a canoe with a series of paddles fanning out from the boat's bottom. Each paddle is imprinted with the name of a Rockfish financial partner, a fitting tribute for a place that has a polished floor littered with discarded peanut shells.

The name Rockfish is derived from the seafood menu in tandem with river-rock walls that line the entrance, bar, and counter areas plus the 1940s-style ROCK-OLA jukebox by the bar. The menu is nearly identical to Shell's, but its execution is far smoother. Gumbo with chicken, shrimp, and sausage had a good smoky flavor with generous, moist chunks of chicken and firm, tender rice. But the roux could use a bit more savory richness and a firmer spice kick.

Peel-and-eat shrimp, served in a tin bucket of ice, were cooked to a perfect firmness, while the boil used in the preparation brought out all of the shrimp's natural sweetness without masking any of its flavor.

But freshly shucked oysters on the half shell were fairly mushy, with tired flavors and little clean brininess. Two from our dozen had some pretty severe off flavors, the kind that make you think there's a contract out on you.

The buffalo shrimp po' boy seemed a misappropriation of flavors to my buds. The sharply sour spiciness of the buffalo sauce trounced the sweet popcorn shrimp flavors, and the breading got pasty and gooey in the sauce after just a few minutes in the flavorless, chewy roll.

Rockfish's entrees feature fish, shellfish, daily pasta and fish selections, plus "things that don't swim"--a small selection of meat and chicken. The fish specials are quite good.

Though slightly spongy, the grilled sea bass with lemon-pepper butter was overall flaky and suffused with clean, mildly sweet flavors. A side of grilled zucchini, yellow squash, and broccoli was perfectly prepared. But a side of rice, though adequate, was dry and needed seasoning to stand up to the rest of the plate.

Rockfish's crab platter was stellar. Generous servings of snow crab were firm, succulent, and screaming with rich, sweet flavor. They've either tweaked the recipe, found a better supplier, or improved kitchen execution, because this stuff is markedly tastier than the crab served at Shell's. A side of spicy sausage provided a gripping, aggressive counterpoint to the more delicate crab. But corn on the cob didn't receive the same attention to detail as the rest of the platter and was inexcusably soggy, mushy, and mealy.

With a crispy exterior, the grilled salmon was a little on the dry side and slightly bland. The vegetables were perfect again--and the rice dry and roundly boring--proving that Rockfish is consistent if nothing else.

Fortunately, there is some substantive "else" to this place. The menu isn't killer, but it has points of luminosity that seduce. And with reasonable prices and an attitude that exterminates any pretentiousness that might soil its peanut-shell-cluttered interior, it's hard to quibble too loudly with its culinary shortcomings.