SIR RICHARD BRANSON has a hangover.

It's a sweltering Sunday morning in Baltimore, and Branson shambles in to meet me for breakfast in the tony Explorers Lounge of the InterContinental Harbor Court hotel. He says he tied one on last night after the Police show at the Virgin Festival, and now he's a bit worse for wear. As a morning tonic, he orders tea and nibbles on a wedge of dry toast.

"For the past several weeks I've been keeping to my island in the Caribbean, staying clean, no drinks," he says. "You know, swimming, kiteboarding, staying fit. But then you get an occasional...relapse." He pulls a scowl of mild self-reproach and adds, "I might have broken a few rules last night."

Branson is wearing jeans and a simple black T-shirt, his long strawberry-gray locks still wet from the shower. His eyes are bloodshot, and his famous toothy smile is not yet open for business. Right now he doesn't look much like the chairman of the Virgin Group, an international empire that consists of more than 200 companies and employs some 55,000 people across the blue planet. And yet, you have to hand it to him: The man seems astonishingly well preserved for a 57-year-old risk taker who has crashed balloons, survived shipwrecks, bailed from doomed aircraft, speedboated across the stormy Atlantic, partied for decades with lizard-skinned rock stars, and courted more permutations of harm than anyone but Evel Knievel could imagine.

Branson informs me that his son, Sam, a 22-year-old sometime model who is Virgin's heir apparent, will not be joining us for breakfast, as had originally been planned. It seems the young Branson attended the same bash and is now out of commission for much of the day. "He's a good lad," Branson says. "You'll like him—if he ever wakes up."

Now Branson gazes out the window, toward Baltimore's boat-filled harbor, with its celebrated aquarium, and tries to get his motor working. We talk for a while about his interest in low-orbital commercial aviation (New York to Australia in less than an hour!) and the privatization of the cosmos (Virgin hotels in space!). We talk about some of his friends—Nelson Mandela, Stephen Hawking, Peter Gabriel—and about the Arctic dogsled expedition he and Sam made this spring on Canada's Baffin Island. We talk about Branson's extraordinary life, extraordinary year, extraordinary week. (Just a few days ago, his newest corporate child, Virgin America, made its debut flight to San Francisco from New York.)

But it's simply too early in the morning. The Bransonian magic won't kick in; the fog refuses to lift.

Now he says the chauffeur is waiting outside to whisk us away to the Virgin Festival. Branson has invited me to tag along today as he does a semichoreographed dance of meetings, press conferences, and backstage photo ops surrounded by a sea of more than 74,000 sun-addled festivalgoers. The Virgin Festival is a sprawling, two-day rock concert set in the infield of Maryland's Pimlico Race Course, with three stages cranking out nonstop music from bands like Wu-Tang Clan, the Beastie Boys, and the Yeah Yeah Yeahs. But it's also a kind of eco–big tent designed to showcase the Virgin Group's new green thinking. Branson has come here from his energy-efficient hideout on Necker Island in the (where else?) British Virgins to throw the weight of his persona behind the conglomerate's carbon-neutral message.

"I'm not entirely sure what I'm supposed to be doing today," Branson confesses. "But someone will point me in the right direction."

Even as he says this, two of his Bond-girl handlers (are there any unattractive people working for this company?) hover in the wings of the InterContinental's mezzanine, motioning for him to wrap up our breakfast. Hangover or no, the Branson Machine must get a move on. His chariot awaits.

But when we walk downstairs to the lobby, I'm a bit confused. There is no limousine, stretch or otherwise. No bodyguards or bouncers. No retinue of sycophants. I had secretly hoped we would be boarding a smoke-hazed tour bus with Ben Harper or the Smashing Pumpkins. I had imagined rolling hot tubs, dry martinis, and (if Sting happened to be on board) marathon orgies of tantric sex. But all I can see, parked out in the valet lot, is a staid, corporate-black Prius, idling in silence.

"Brilliant—that's our car," Branson says. "C'mon, let's make for the show."

And so we hop in—Branson in the passenger seat, me in the back with Holly Goodhead and Alotta Fagina—and the driver takes off through the traffic snarls of downtown Baltimore.

"God, I hate the sound of engines," Branson says. "All the fleet vehicles we use at the Virgin Festivals are either hybrids or flex-fuel cars— it's in our contract. These Toyotas are massively sexy, don't you think?"

On this 90-degree August day, riding through the wavy Chesapeake heat, no one recognizes the multibillionaire knight as he coasts on Japanese battery power toward his own personal rock concert.