The world is a different place than it was when Napoleon and Winston Churchill had their suits made on Savile Row. So while the recent addition of a flagship Abercrombie & Fitch to the famous London street felt both disheartening and slightly sacrilegious, it was not, as even the old-school tailors who lined the sidewalks in protest would admit, all that surprising. And yet there are still occasional gleams of hope: At least one warrior is pushing back—to the bespoke tradition.

"We never wanted to look like the old tailors," says Richard James, whose shop has been at the heart of Savile Row since 1992. "We were a breath of fresh air. Our walls were white. Our door was open." And the clothes were revolutionary. He sold clubby gray cashmere suits—albeit with a lighter, more stylish fit than those offered by his neighbors. There were also beautifully crafted green seersucker suits and wildly colored socks made of the best materials.

Now that Abercrombie has thundered into town, James wants his new bespoke shop on adjacent Clifford Street to change the game once again. Naturally the new outpost will carry contemporary made-to-order suits crafted by experienced on-site tailors whom James—at six foot one and just shy of 50, smartly attired in his own designs—had to scour London to find. (His old address will henceforth focus on off-the-peg suits, which start at $1,350; bespoke ensembles run upward of $5,600.) The extension will offer other creations that aren't endlessly replicable, like a set of 30 "slightly eccentric but utterly English" shirts or six pairs of never-to-be-duplicated diamond or sapphire cufflinks. Fittingly, edgy-meets-established also characterizes the atmosphere. Since the sixties, Clifford Street has been the province of small, daring tailors. The mid-19th century townhouse James found sits opposite the fabled Bucks Club, known for the Bucks Fizz and for reputedly having had just one female member: the late Queen Mother. (James's upper windows even offer a view into the exclusive enclave.)

The British actor Hugh Dancy was drawn to James's singular clothing. Perhaps best known for playing the Earl of Essex in Elizabeth I opposite Helen Mirren (or for those ubiquitous Burberry ads with Kate Moss), Dancy says: "They're beautiful—well-cut, classic, but you wouldn't just wear them to the office. Shops like this show how Savile Row is redefining itself. And that's how it survives." For inspiration, he looks to Sean Connery (circa Goldfinger) or Cary Grant (circa always), and he says he is "never quite as casual as I think I am—I love a well-made jacket." Bespoke selectiveness is also a hallmark of his role choices. He spent this past spring on Broadway in the World War I drama Journey's End, a return to his stage roots, and he can currently be seen as the drunk, rich, and befuddled Buddy Wittenborn in the time-leaping Evening, which co-stars his girlfriend, Claire Danes, and Meryl Streep, with a script co-written by The Hours author, Michael Cunningham.

England loves its institutions, from the Queen's corgis to Fortnum & Mason's hampers, and this Richard James astutely understands. In a nod to Savile Row's formative days, the otherwise forward-thinking designer has ensured that his shop will operate in the old tradition, tailoring its services as well as its suits and shirts to each patron. James has chosen to run his empire from an office only a few steps upstairs from the new store. "That way," he says, "I can stay close to the clothes." And close to the discerning customers who will continue to seek him out, even if they have to scissor through cargo pants and faux-vintage T-shirts to find him.—CHARLES FINCH

Richard James, 19 Clifford Street, London, W1, 011-44-20-7434-0605; richardjames.co.uk.