PHOTOGRAPHY BY ERIC LAIGNEL

Two years later, Chicago's star-rated Charlie Trotter failed to make his much-anticipated Manhattan debut in the third-floor space allotted to him. So the real-estate developer Related Companies asked Marc Murphy, the chef-owner of TriBeCa's bustling 100-seat bistro Landmarc, to take a look at the 10,500 square feet available. When he glimpsed the vast sweep, he admits, he "got nervous."

Nevertheless, even before the 110-page 20-year lease was signed, Murphy hired Interior Design Hall of Fame member Clodagh at the suggestion of Pierpont Architecture's Robert Pierpont, who'd worked with Murphy on the first Landmarc location. ("If Marc weren't a chef, he would be a designer," Clodagh says.) Then, to inspire the team—Clodagh's "family," as she likes to call it, and Pierpont as architect of record—Murphy hosted a series of tasting dinners at the TriBeCa restaurant, so everyone could get a feel for the Landmarc look: exposed brick walls, sanded wooden beams.

Over warm goat-cheese profiteroles and marrow bones with onion marmalade, plus a special plate of spinach, ratatouille, and leeks vinaigrette for Clodagh, who's a vegan, Murphy explained to the group that the challenge would be "to remember we won't be in an old building." Clodagh interpreted this, she continues, as "postindustrial but not in a Disney-esque way." And she introduced the natural elements she believes keep a design grounded: water, fire, earth, wood, and metal.

Structural columns are wrapped in raw steel, and the tops of mid-height curved steel partitions are chopped at the angle of a "Grace Jones flat-top," Clodagh says. "It's not quite Richard Serra, but you get the feeling." Flooring in the dining room is 5-inch white-oak strips with a medium stain. The restrooms' brown porcelain floor tiles are the major earth element. "They were born for me," Clodagh enthuses. "When I first saw them, I cried." Also earth: the veneer bricks set, with intentionally untidy grouting, above the ribbon windows and around the open grills. As grilling steaks flare, there's the fire. "The whole thing is quite funny for a vegan," the designer adds—going on to tout Landmarc's grilled portobello mushroom.

The biggest gesture is a little sleight of hand. What appears to be a sea of monster rebar suspended from the ceiling is actually 9,000 linear feet of cast-fiberglass replicas similar to ones used for railings in TriBeCa. Here, they're slightly overscale to look right hanging 10 feet up in the air—and the lighter material makes it much safer if one should happen to fall.

Clodagh's persona may be all earth mother and feng shui, but she says she selected the banquettes' "joyfully synthetic" microfiber upholstery partly for its low coefficient of friction—sliding across is easy—and also for ease of maintenance. As project director Chris Marta says, "Clodagh's inner housewife made several appearances." And she agrees: "My inner housewife was all over the place."

Ditto for her inner grease monkey. At the far end of the long dining room, overhead glazed garage doors can close off two spaces for private events. The manufacturer initially refused to understand why divisions between the glass panes of the doors should line up with the Time Warner Center's window mullions. ("Behind every no there's a yes somewhere," Clodagh says brightly.) Murphy points out how the doors' glass sandwiches a layer of stainless-steel mesh, Clodagh's innovation in privacy. At the other end of the dining room, the one with a sliver of a Central Park view, Clodagh added visual interest by cladding a sidewall in blackened steel, then peeling away vertical strips to expose LED mood lighting in a soft amber tone.

With seating installed for 300, a total of 800 folks passes through daily—from 7:00 AM to 2:00 the following morning. Some of them, Murphy reports, are his TriBeCa regulars temporarily migrating uptown. And then there's an imaginary guest. Marta pictures Tony Soprano gravitating toward the freestanding round booths—tubs of rolled steel, some with bronze-colored upholstery inside. These pods were a response to the huge popularity of their single predecessor in the downtown restaurant. They're so popular, in fact, that Murphy requested two large enough to seat eight. Marta has christened them the Mega Gandolfinis.

PROJECT TEAM: TAL GELLER; GILLES-FLEUR BOUTRY; OMAR CLENNON; ASHLEY HERMANN. BANQUETTE FABRIC, POD FABRIC: POLLACK (SEAT); SINA PEARSON (BACK); WOOD, SPRING & DOWN (UPHOLSTERING). CUSTOM CHANDELIER: BODNER CHANDELIERS. LOW STOOLS: THROUGH ABC CARPET & HOME. CUSTOM OVERHEAD DOORS: UNITED STEEL PRODUCTS. CUSTOM DINING TABLES, CHAIRS, BAR STOOLS: CHAIR-UP TAKAHATE COMPANY. RECESSED CEILING FIXTURES: LITES. FLOORING: RMD FLOORING. GLASSWORK: CLIFTON ARCHITECTURAL GLASS & METAL. BRICKWORK: ALL CITY STONE. METALWORK, FIBERGLASS WORK: J. FREDERICK CONSTRUCTION. CONCRETE WORK: ROBERT YOUNGER. LIGHTING CONSULTANT: ZEROLUX. AUDIOVISUAL CONSULTANT: AUDIO, VISUAL, AND CONTROLS. STRUCTURAL ENGINEER: CANTOR SEINUK GROUP. MEP: THOMAS J. FISKAA ENGINEERING. GENERAL CONTRACTOR: SHAWMUT DESIGN AND CONSTRUCTION.