(FORTUNE Magazine) – On the bustling floor of the Detroit auto show, the Bentley Continental T Mulliner coupe was easy to miss: another expensive, dark-green two-door, its squarish lines a decade out of sync.

But this Bentley is ahead of the curve. Over the next several years, hand-built cars priced above $150,000 will be rolling onto freeways at what, for them, is a hectic pace. Mercedes is developing the $300,000 Maybach, first shown in Detroit in 1998, bringing back to life a name that drew sharp breaths of respect in 1930s Europe. Porsche is preparing the $350,000 Carerra GT; only about 500 will be sold. Bugatti, Lamborghini, and Aston Martin also have new vehicles in the works.

The miniboom is aimed squarely at the growing number of newly rich, says Autodata analyst Ron Pinelli. The typical owner is a male CEO or entrepreneur who earns at least $3 million a year, owns four houses, is well past his first marriage, and often pays cash. "At this price," says Pinelli, "it isn't a car anymore. It's a piece of jewelry."

Despite the surge, the market remains exclusive. Bentley built only 2,200 cars last year, including 520 Rolls-Royce models. (Volkswagen, which acquired the company from Vickers for $800 million in 1998, will give up rights to Rolls-Royce to BMW next year and concentrate on Bentley. BMW plans its own factory for Rolls-Royce.)

The starting price of a Mulliner--there are 290 in the world--is $315,900. Note the word "starting": Bentley's personal-commissioning staffers can customize it from tires to trim. The team decked out the car on display in Detroit with special side-panel air vents with vertical louvers, a quilted-leather interior, and a set of suitcases that sit in their own holster. These and other extras tip the price to $465,000--about what you'd pay for four Mercedes S-Class sedans. (If you can't afford a Mulliner, just wait. The relatively cheaper MSB--or midsized Bentley--is due in 2002. It's a bargain at $170,000.)

How can a car cost so much? The answer lies at Bentley's picturesque 55-year-old factory in Crewe, England. For anyone used to sprawling, high-tech auto mills, the Bentley plant is a revelation. The difference is visible even from the outside: In an Edwardian touch, some employees ride to work on bicycles, which they park in racks near the doors.

Inside, there isn't a robot to be seen--just a bit of automation back in the paint shop--and every step along the assembly line brings a new example of meticulousness. Along one corridor sits the leather shop, where custom-dyed hides (each car requires 15) are cut individually. The skins come from cows, ostriches, deer, even goats; there's cavalry twill for the leather-averse. Bentley will copy any color, and has been asked to match a dried rosebud and a single sequin. Wilton carpet, woven to order, gets the same attention.

A few feet away, a dozen workers scrutinize a painted car body, tipped up on its left side. Two canisters sit nearby--one of black paint, another of oozy tar. No Bentley leaves the factory with any bit of exposed metal. The undersides are coated with corrosion-resistant black paint, and again with a sealant. The job of these employees is to touch up any missed spots, using a long-handled brush.

The attention to detail is particularly apparent in another building on the grounds. Here, every bit of wood and metal used on the cars is cut, lacquered, and polished by hand, from the Bentley hood badge to the dashboard. Forget a smooth grain--Bentley wants swirls and knots and waves. The quest can go a bit far: After polishing one piece of the instrument panel, craftsmen discovered that the knots had formed a ghostly face with a Munch-like shrieking mouth. Too frightening to be sold, the section now hangs in a factory doorway.

Each piece of wood then receives three coats of lacquer, which must dry for two to three days. That's sanded down to an even appearance, covered with beeswax, and polished by hand. Above the shop floor is a sign: WOOD HAS LIFE--WE GIVE IT SOUL.

Do Bentley owners really appreciate all this? The 3,000 members of the Bentley Drivers Club do; they meet at the factory each year to drive Bentleys old and new, donning waxed Barbour jackets to picnic off rubber-backed woolen rugs on the grounds of great English country houses.

Others are simply out for what a Bentley tells the world about them. "It isn't a question of the product," says analyst Pinelli. "They aren't buying this car because it's mechanically better. With Bentley, they'll have this image to convey about their affluence, their success." And in coming years, given the ultraluxury miniboom, a few more lucky souls can claim that privilege.

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