High-profile restaurants have been opening in an unceasing succession lately, but none has been as keenly anticipated as Laurent Gras’ dreamy undersea sanctum L2O or Graham Elliot Bowles’s refuge from the corporate lockup at Avenues, Graham Elliot.

Of the two chefs, the impeccably pedigreed Gras—who worked under the titanic Alain Ducasse in Paris before making his name in New York and San Francisco—invites more skepticism, as he’s riding the midwestward wave of carpetbagging chefs breaking on the shore of our anointed culinary capital. But with L2O, given a ghetto pass from Rich Melman and the old Ambria space to work in, he’s executed an encompassing vision (documented since December on an absorbing blog, l2o.typepad.com), orchestrating everything down to the most minuscule element to provide a thoroughly transporting dining event.

Architecturally, the latest Lettuce Entertain You project evokes a twilit submarine fantasy world where the creatures at the top of the food chain are rewarded with the finest little fishies, many shipped at great expense from where they’re pulled from Japanese waters (see your check) and all prepared using an integrated battery of classic techniques and modern innovations. One could go on and on listing the ways L2O has advanced the cause of eating in Chicago. There’s the in-house bread (and butter) program, featuring a half dozen varieties, the ultimate achievement among them the buttery, light anchovy brioche I’d devour even if they were attached to fishhook and line. There’s the 26-year-old sommelier prodigy Chantelle Pabros, whose unguarded passion for her selections is breathtaking (ask her about the sakes). There’s the flawlessly professional service that’s simultaneously relaxed and relaxing. And then there are the chef’s creations. Whether you order the four-course prix fixe menu ($110) or the dozen-course tasting menu ($165), the progression begins with raw courses and moves on to warm and cooked ones in increasingly dramatic presentations. (There are also “singular” items available a la carte.)

I tried the tasting menu, and in general I preferred the early raw courses and amuses, usually exceedingly fresh pieces of fish judiciously accented with brilliant but not overpowering flavors: for example, a touch of the Basque chile powder Espelette with a crab ceviche, or a bite of tuna tartare and a slice of cured foie gras kissed with a bit of chocolate and tomato gelee. Not that I wasn’t awed by the later courses, but those were the only ones in which I could find anything I didn’t like, and in most cases I was reaching. Among the most enjoyable: a textural duel between madeira-marinated morels and a fat diver scallop and a halibut fillet with a side of a rich, cheesy aligot drizzled by the server with a zesty tomato-Chablis bouillon. Like that halibut, many courses are finished tableside on wheeled gueridons, the delicate broths and sauces applied with a flourish—just some of the many gestures calculated to maximize the intimacy of this most rare of experiences, one that continues to haunt me three weeks down the road.

Unlike the new guy, the cherubic, down- to-earth Bowles is a known quantity, a homeboy (more or less) who helped make Chicago a draw for chefs like Gras. Now at Graham Elliot, hasn’t he earned the freedom to crank his iPod, outfit his staff in T-shirts and Chucks, and cook with Cheez-Its and ironic cheap beer? Big windows, wood pillars, and exposed brick and ductwork mark this declaration of independence, but there’s a thread of narcissism woven throughout the place that becomes distracting.

Squint past GEB’s not entirely legible handwriting and you’ll find the menu is divided into “cold,” “hot,” “sea,” “land,” and “sweet” courses (with corresponding wine suggestions), which are scattered with artifacts from a late-20th-century history of industrial snack foods. A deconstructed Caesar salad seems to be positioned as a signature dish, but its most original element, a “brioche Twinkie,” is like something pulled from the day-old bag at the neighborhood panaderia. This sort of nostalgic twist was cute in the Pop Rock “foielipop” (conceived at Avenues and available on the bar menu here), but fond memories of indiscriminate drinking don’t make bitter Budweiser foam delicious. That’s an accent on a spicy buffalo chicken dish with competitively aggressive hot and blue cheese sauces. It’s expensive for what it is, at $13, and it lacked balance, as did a cheddar-apple risotto with a predominant bacon flavor (from “powder”) that a sprinkle of Cheez-Its did nothing to enhance.

Rice Krispies, PBR, malted milk balls, and Nilla wafers also show up in various forms. Sometimes the gimmicks are just jarring—like a scoop of hickory-smoke-flavored ice cream that brought a taste of ashtray to an otherwise delicious Kobe beef tartare. We had better luck further down the menu: a relatively simple pan-roasted skate with caper-raisin chutney and an insurmountable but tasty double-cut Berkshire pork chop with barbecue sauce and a crunchy watermelon chutney. But too many dishes seem overearnestly calculated to provoke some nostalgic reaction, and it gets mawkish fast.

Not even the house cocktails show much balance: the London Calling, a riff on a Pimm’s cup, was all gin and ginger up front but nothing on the bottom, and a sangria mixed with carbonated port and a tempranillo sorbet was like a small tumbler of fruit jelly. As much as I’m pulling for Bowles, I knew there was something wrong when I found myself commenting more on his playlist than on the plates. His attempt to informalize fine dining feels far more forced than the graceful, comprehensive execution at L2O. Neither restaurant is cheap, and especially not L2O, but at least there you get what you pay for.v

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