Dean Potter is having a bad day. It's a blue-sky, late-June morning in Yosemite National Park, and the rock climber is supposed to be up on El Capitan. His plan was to become the first person to walk a highline—basically a wobblier version of a circus tightrope—from one rocky ledge to another along the 3,000-foot-high, legendary cliff face, but he stayed out all night with friends and is in rough shape. Now he's standing at El Cap's base, bleary-eyed and reeling from the implosion, just minutes ago, of his five-year marriage to pro climber Steph Davis. After a tense, two-hour showdown, Davis packed her truck, collected their dog and headed home to Moab, Utah, leaving Potter to call off the day's highlining project.

It's the latest drama in what—on paper, at least—has been a very bad year for Potter. In May 2006, after making the first known ascent of Utah's Delicate Arch (the sandstone span on the state's license plate), Potter found himself in one of climbing's more heated controversies. Park officials accused him of breaking the law and damaging the arch during his covert ascent, and fellow climbers lambasted him for giving the sport a bad rap. Since then, a federal grand jury has been investigating whether his climb violated federal law. In the wake of the controversy, though no indictments have been handed down, Potter lost two major sponsors and, by the looks of it, his wife.

"Meet me tonight," he says apologetically, shoving his hands into the pockets of his frayed jeans. "I'll have some juicy details to tell you." It's an uncomfortable moment. Potter's clearly upset, yet he's trying to salvage an interview with the promise of dirt.

There are many adjectives to describe the 35-year-old, but the best might be unpredictable. Potter is one of the world's best climbers, with strength and determination on the rock that border on superhuman. He's also a typical bad-boy athlete who can't stay out of trouble. He can be disarmingly friendly and forthcoming one day, cliquishly aloof the next. He has all the trappings of a dirtbag climber—seasons-old clothes, tortilla-and-cheese subsistence diet—yet by the sport's standards he's loaded, a real estate baron with his house in Moab, and a rental property and two empty lots in a high-rent Yosemite neighborhood.

But the oddest Potter paradox is this: Although his world seems to be crumbling around him, he's never been more on his game. In the past 18 months, he has accomplished some of the biggest feats in adventure sports. Potter has evolved from rock climber to hybrid pioneer, pushing boundaries in three risky pursuits: free-soloing (climbing without safety ropes); BASE-jumping (parachuting off buildings, antennae, spans or earth formations); and highlining. "I've sent major projects every month or so for the past year," he says, "and I feel like I'm approaching a breakthrough." Like Deion Sanders and Jeremy Bloom, Potter switches effortlessly from one sport to the next, sometimes in the same day. But in Potter's case, one misstep could kill him.

Potter taught himself to climb during high school in southern New Hampshire. A gangly and rebellious Army officer's kid, he started by scaling the chimney at his best friend's house, then graduated to a nearby 200-foot cliff, cutting classes to free-solo the granite route in his Chuck Taylors. When he left for UNH in 1990, Potter gave up climbing to row varsity crew under a tyrant coach whose philosophy was, "You don't just want to beat the guy. You want to own him." That was fine until one day Potter went climbing again and decided he didn't want to own anyone. The next day, he dropped out of college to become a climbing bum.

Potter spent the next decade touring the West, living in his van and working greasy diner jobs to support his climbing habit. By 2002 he'd become one of the world's best rock climbers. A deal with Patagonia paid him nearly six figures a year, and he picked up smaller sponsorships from gear companies such as Black Diamond and Five Ten. He got married. He landed national magazine covers. He developed a reputation as a soul climber, dedicated to the sport not for cash or glory but for the pure joy of being on the rock. By all measures, he'd made it.

Yet there was one problem. Potter had a recurring dream in which he was barreling through the air. Far below stood a dead tree, and a persistent tug yanked at the hollow place between his shoulders, pulling him upward at the same time that he was falling. Convinced it was a premonition of his death, Potter tried a perverse tactic: He sent risky free solos and highlines in Yosemite. "I thought if I was going to die, I wanted it to be on my terms," he says. He took up BASE-jumping, hurling himself off cliffs and deploying his parachute seconds before impact. The feeling he had when the canopy caught him—pulling him up by his vertebrae until he was floating—felt weirdly familiar. Then he realized he'd been wrong. In his dream he wasn't dying, he was flying. And that's when the insanity really began.

Of Potter's three disciplines, highlining is arguably the most difficult. It's certainly the most obscure. Highlining is a more radical version of slacklining, which was invented in the early 1980s by rock climbers looking for ways to kill time at base camp. They strung chains and cables between trees several feet off the ground and walked barefoot from end to end. Later they switched to nylon webbing. Unlike in tightrope-walking, from which slacklining developed, the lines are dynamic, or "slack," not tight and static; the farther you are from the anchored ends, the more the line vibrates. And while circus walkers hold poles for balance, slackliners use only their outstretched arms and concentration to keep from toppling off.

By the mid-'80s, a small group of Yosemite climbers had begun rigging slacklines higher and higher above the ground, and highlining was born. Today, Potter is one of a handful of highliners skilled enough to walk the high-est of lines and the only one in the world who walks without a safety leash. Sometimes he makes concessions when outsiders are present, using safety ropes during photo shoots or filming, for example; that way, people watching for the first time don't get anxious and break his concentration. But during a typical solo highline, Potter must catch the line with his hands or legs if he falls. Otherwise, he'll plunge to his death.

Potter's creative frenzy began shortly before his May 2006 Delicate Arch dustup. In Arches National Park, not far from his home in Moab, he walked two 50-foot highlines suspended 400 feet above the ground between three blocky spires. For three days, from sunrise to sundown, he traversed their length more than 100 times. When he slipped, once, he snagged the webbing with one knee and corkscrewed back onto the line.

A few days later, Potter summited the Titan, a 900-foot sandstone tower near Castle Valley, and jumped. "Three, two, one … see ya!" he hollered. The sound Potter's body made in free fall was deafening, a whistling screech that roared louder as he descended—like a refrigerator heaved off a 90th-floor balcony. Plunging chest first, arms stretched wide, Potter neared terminal velocity, deployed his chute at 400 feet and let it sway him gently to the ground.

At dawn the following day, Potter inched his way up the bulging east leg of Delicate Arch. The sandstone span, propped on a skinny isthmus of slickrock between two canyons, looks terrifyingly precarious. Ropeless, Potter felt the flaky face for dimples—tiny finger- and toeholds. If he slipped, he'd plunge 40 feet to the base, bounce, then fall hundreds of feet more to the canyon bottom. He free-soloed the Arch several times as the sun rose.

He didn't fall, but the Arch ascent unleashed an avalanche of criticism from fellow climbers and park officials, while sponsors Patagonia and gear company Black Diamond dropped him. They claimed that Potter denigrated the iconic rock when ropes used for practice and staging left grooves in the soft sandstone; all agree that he ruined access for future climbers. At the time of the climb, park regulations stated that named arches "may" be closed to climbing; two days after the climb, they were declared off-limits. "The public's response made me feel like I don't know our society's norms anymore and that I'm a little disconnected," Potter says ruefully. Still, he's not all that sorry: "People think that in order for nature to be sacred, you have to separate yourself from it. It was so beautiful, I'd like to go up there and do it again."

He hasn't, but over the following year, Potter completed a quartet of nasty Yosemite free-solo climbs, including the first solo of Heaven, an overhang with 2,600 feet of exposure. "If you fall," says Potter, "you're not going to die immediately. You're going to hit the slab below and try to cling on and claw your hands off for hundreds of feet, and then you're going to free-fall for thousands of feet."

Despite evidence to the contrary, Potter doesn't have a death wish. "I don't think he's surrendered to the possibility of death in any way," says longtime friend Brad Lynch, whose short film on Potter, Aerialist, was released earlier this year. "I think if Dean blows it, his last feelings are going to be complete disappointment in himself."

Says Potter: "I don't have thoughts of an afterlife. I think dying is like when you swat a fly—it's over." Potter doesn't want to die, he just wants to come as close to the brink as possible. "I'm addicted to the heightened awareness I get when there's a death consequence," he says. "My vision is sharper, and I'm more sensitive to sounds, my sense of balance and the beauty all around me. A lot of my creativity comes from this nearly insane obsession. Something sparkles in my mind, and then nothing else in life matters."

Shortly after 9 p.m. on the night of the abandoned El Cap highline, Potter wanders into the bar at the 80-year-old Ahwahnee Hotel, Yosemite Valley's swankiest address, wearing flip-flops and sagging jeans held up around his concave waist by a piece of climbing rope. Even for those who don't know he's a world-famous climber, Potter is hard to miss, at 6'5" and 185 pounds, with a prominent, patrician nose, and wavy, male-model dark-brown hair that hangs in his eyes. He walks with a nonchalant slouch, hips first, as if his middle were made of rubber. Surrounded by sunburned tourists in tube socks and Timberlands, he radiates a quiet, self-contained intensity.

He settles in with a pint of Sierra Nevada Pale Ale and, as promised, starts to talk. It turns out the dirt he's dishing tonight is about himself. With a straight face, Potter explains that his dogged pursuit of athletic excellence is all part of a loftier goal. To fly.

Potter's plan goes like this: He'll build strength by climbing tough routes and hone his focus by highlining, BASE-jumping and free-soloing projects that require him to enter a trancelike state. "I'll be balanced mentally and physically, and hopefully it'll all funnel together into this superheightened power to fly," he says. "That's all I think about."

Potter has always been headstrong, modeling himself on eccentric mind masters with great powers of concentration, like French tightrope artist Philippe Petit, who walked between New York's Twin Towers in 1974, and 17th-century samurai Miyamoto Musashi, who, legend has it, could control the minds of enemies. Potter downplays his physical strength, insisting it's his laserlike internal focus, inspired by Zen meditation and martial arts, that separates him from peers and keeps him alive. During high-risk solos, he uses a deep-breathing technique cribbed from kung fu. "When you're combating your opponent, you're more likely to strike a lethal blow on his inward breath," he says. "So I start exhaling, and everything else fades away."

Aerodynamically, of course, self-propelled human flight is a nutty proposition. Potter, like many BASE-jumpers, often wears a one-piece, bat-shape, nylon wing suit that allows him to extend his horizontal glide during a jump. Wing-suiting, or "bird-manning," is the closest approximation humans have to real flight. But it's not the sort of soaring Potter has in mind. What he's picturing is an actual human body—his—taking a running start, achieving liftoff and, well, flying. With nothing but his own two arms as wings. Just like in his dream.


"I know it's insane to think that I could fly," Potter says. "But to make it possible, you truly have to believe in it—to go to a place that's not accepted."

Potter, by all accounts, has never abandoned a project because of its supposed impossibility, and he's not willing to start now. He did finally traverse the El Cap highline—at 2,700 feet, his highest ever—in early July, and he's busy plotting the first "free-BASE," in which he'll solo a big wall, like Switzerland's Eiger, with only his parachute as protection. If he falls, he'll have just seconds to steer away from the rockface and deploy the canopy. If he succeeds, it could revolutionize climbing and open legendary routes on El Capitan and Half Dome to free-soloing. Then there's his plan for ski-BASEing—soaring off the Himalayas' steepest peaks with only a parachute and skis.

There's almost no end to the combinations Potter can dream up. For better or worse, drama is what drives his creativity. "The real trick isn't the trick," says Lynch. "The real trick—and the trouble for Dean—is to do the trick and not alienate himself from humanity. To stay out of jail. To stay in relationships. To stay alive. Maybe he's on the edge of another breakthrough, but we'll see if anything worldly survives."

Potter and Davis reunited briefly in July and then again in October, but their relationship has always been rocky and there's no predicting what will happen next. In the meantime, every ascent, every BASE-jump, every highline takes Potter just a little closer to that transcendent place where body and mind are at their peak at the same time, when his whole world snaps into focus.

When anything, everything, is possible.