“WHAT'S THAT CRAZY GUY UP TO NOW?”

Caballo Blanco Caballo Blanco in Mexico's Copper Canyon

It was amazing and almost reassuring to hear photographer Luis Escobar now sounding so calm and lighthearted, because his first reaction when he heard that our friend Micah True was missing in New Mexico’s Gila Wilderness was to grab the keys of his wife’s Chevy Tahoe, tell her, “I’m going,” and start barreling south from Santa Barbara, California on a 1,000-mile rescue mission. Texting while he drove, fighting his way through rush-hour traffic, Luis was steering with his knees while coordinating an all-points-bulletin with his thumbs.

I was in Los Angeles for an event that day, and while Luis was on the freeway, I was getting the rundown from Micah’s girlfriend, Maria. On March 27, she told me, Micah had set off for a run in the Gila and hadn’t been seen since. It was Thursday now, and I heard Maria’s distress, but c’mon: it’s Caballo Blanco we’re talking about, the wandering White Horse of Mexico’s Copper Canyons. As I wrote in Born to Run, the Horse has been roaming some of the trickiest and most inhospitable terrain in North America for decades, and no matter what kind of trouble his restless eye got him into, his legs always got him back out again. If Caballo wasn’t lost, he wouldn’t know where he was.

In fact, he’d just gotten lost on the day I met him in 2005. He’d set off for an easy hike that morning from Creel, a Mexican town on the fringe of the canyons, but got sidetracked by a tasty trail, started running, and ended up bushwhacking the Copper Canyons outback until he finally got his bearings just before nightfall. "I'm always getting lost and having to vertical-climb, water bottle between my teeth, buzzards circling over head," Caballo told me. "It's a beautiful thing.” That’s been the story of his life, stretching from his discovery of running during his backroom fight-club days in the 1980s — the same era when a fellow-wanderer named Smitty found him roaming the Hawaiian rain forests and showed him a secret cave he could make his home — right up to the present, when he’d recently pissed off some bandit named Jorge down in the Copper Canyons and had to blaze a new route along the edge of a cliff to avoid him.

I knew that this time, Caballo must have gotten an urge to spend a few nights in the Gila cliff dwellings, or had strayed out of the wild and onto the highway and was hitchhiking back to the lodge at that very moment, or was behind bars after locking hard heads with a park ranger and was too stubborn to phone for help, and I was about to tell Maria so when she said:

“I just wish Guadajuko was with him.”

Uh oh. Guadajuko, the “ghost dog,” was a half-wild Mexican mutt that Caballo had adopted down in the canyons three years ago after rescuing him from a river. They’d been inseparable ever since. The last time I saw Caballo, in Boulder, Colorado, Guadajuko had a cast on his leg from getting clipped by a bus. Caballo was carrying him around like a baby. No way Caballo would dither in the woods if Guadajuko was waiting for him. I cancelled my flight home from L.A. and got on the phone to Luis.

By the time Luis picked me up three hours later, he already had two other volunteers with him and a third was waiting at our next stop. We soon had to take the wheel and put him in the back seat, because his cellphone kept pinging all night with fresh offers of help: ultrarunning legend Scott Jurek was ramming gear into a bag and heading for Denver airport, while Kyle Skaggs — the Hardrock 100 record-holder who barely knew Micah — was already on the road from his farm in New Mexico. When we stopped around midnight to fill the tank somewhere in Arizona, it was free; a woman in Colorado had insisted on Paypal-ing us gas money.

“I keep thinking we’ll burst in on him somewhere peaceful in the woods, and he’ll give us that grin of his,” Luis said. “The one where you can tell he’s thinking, ‘You’re such a dumbass.’”

But Luis was still anxious enough to keep his ear to his iPhone and his Tahoe hurtling down the highway all night.

IF YOU'VE EVER SEEN the photos that Luis took of Scott Jurek flying across the desert alongside the great Tarahumara runner, Arnulfo Quimare, you’ll understand one reason why Caballo means so much to him. Back in 2006, Luis joined me, Scott Jurek, and one of the founding fathers of minimalist running, Barefoot Ted McDonald, for Caballo’s ultramarathon with the Tarahumara that I describe in Born to Run. Only Caballo’s sheer force of will made the race possible; he’d logged thousands of miles up and down the canyons that winter, visiting one Tarahumara village at a time, earning their trust, and ensuring some of their greatest runners would show up at the start line. The magnificent mayhem of that experience created a kinship that hasn’t faded, I think because it brought out the best in all of us: Scott was extraordinarily noble, Luis took the greatest photos of his career, Barefoot Ted’s kindness found him a true spiritual brother, surfers-turned-ultrarunners Jenn Shelton and Billy Barnett bounced back heroically from near-fatal disaster, and I found myself in the midst of both the story and challenge of a lifetime.

Since then, we’ve yoyo-ed in and out of each other’s lives, and Caballo was often the string that held us together. Caballo and Guadajuko would shack up at Luis’s house whenever they drifted through California, while Jenn, Billy, Barefoot Ted, and I crewed for Luis at the Badwater ultramarathon. Barefoot Ted and I became lifelong friends last summer during a magical night when I paced him to the finish of the Leadville Trail 100. Earlier, Caballo had spent a week in Leadville with me and Eric Orton, the “naked running coach” who persuaded me I could reverse years of injuries and showed me how. We ran trails all day and told stories over beer and jalapeño pizza at night, seeing a warm and fun-loving side of Caballo that had been eclipsed during the chaos of the Copper Canyon race.

So it wasn’t surprising we remained friends; the real shocker was the way Caballo was transformed almost overnight from a lifelong loner into field marshall of an international army of online amigos. For decades, he’d lived like a wanted man; he’d bust his hump as a vagabond furniture mover for a few months in Boulder, then drop off the planet the second he’d saved enough for a year’s frijoles. He’d disappear into the Guatemalan highlands or Mexican canyons, spending his days rattling around the hills and inside his own head. Until he was nearly 60 years old, Caballo split his time between a one-room hut in Tarahumara territory and a sleeping roll in the back of a pickup in Boulder. The Tarahumara were his ideal companions: they ran a lot, spoke little, and never said no to a brew.

But after Born to Run, Caballo was the man in demand. Suddenly, he was jetting off to speaking engagements in London and Stockholm and signing autographs at standing-room-only events. He became an accidental icon, and I loved the way it didn’t soften his raw edges a bit. Minimalist movement? He couldn’t care less, even though he’d been moving minimally for 40 years and had adopted the Tarahumara taste for toe-freeing sandals long before FiveFingers were associated with anything besides shoplifters. He remained searching and skeptical, sunny and surly, a true cowboy who picked his own name, went his own way, and was his own horse. When The North Face offered in 2007 to finance the Copper Canyon Ultramarathon he was struggling to keep alive with his cash, Caballo turned them down, afraid his funky festival in the middle of nowhere would become a corporate-bannered monstrosity with its heart hollowed out by expo booths. His reply summarized his life and became his public identity: “Run Free.”

Caballo was the first runner I’d ever seen who busted out big miles in skimpy sandals, and he opened my eyes to the idea that distance running is humankind’s first fine art; for most of our existence, it was the one natural weapon we had in a world dominated by creatures who could out-swim, out-sprint, out-climb, and out-fight us. I was certain when I went down to the Copper Canyons that I really had nothing to learn: I figured the Tarahumara were genetic freaks and my own running days were over due to chronic injuries. Then I meet Caballo, my eerie astral twin: we were the same height, the same shoe size, and the same age when we first encountered the Tarahumara, and he’d also struggled with broken-down legs. He took me into the hills, showed me a few things, and sent me home with the idea that maybe, just maybe, the Tarahumara were custodians of a transferable skill that even an overweight mope like me could master.

That’s why he has fans all over the world. But right when the rest of us were catching up to him, Caballo disappeared.

THE MORE SEARCH AND RESCUE found out about his last known movements, the more bewildered they became. Caballo left Mexico on March 23, driving north in his old pickup toward Phoenix to see his Maria, the “Apache butterfly” who’s been his girlfriend for the past two years. He’d stopped off along the way to visit friends and kick back a little at Gila Wilderness Lodge, a place he’d been many times. Caballo was overdue for some down-time; he’d just pulled off a masterpiece of a race, somehow managing logistics for a field of more than 400 Tarahumara Indians and 80-some American and international runners at the March 4 “Ultramaraton de Caballo Blanco.” Afterwards, everyone headed home while Caballo spent the next two weeks barnstorming the canyons, making sure that the sacks of corn the Tarahumara winners had earned as prizes made it to their villages.

When we arrived in New Mexico on Friday morning, here’s what we knew: on his first morning at Gila, Caballo set off on one of his epic, six-hour trail runs. The next day — Tuesday — he told his buddies at the lodge he only had time for a little 12-miler leg-stretcher before hitting the road to Phoenix. Guadajuko’s paws were sore from the day before, so Caballo left him tied to the porch and said he’d be back in a couple of hours. SAR was certain he then ran three miles right down the center of Route 15 toward the Gila Visitor Center, because drivers remembered swerving around him.

So, the good news: that left only three more miles before he would have turned around to finish his 12 mile out-and-back.

And the bad: after scouring that three-mile perimeter by day with dogs, horseback patrols, and helicopters, and by night with infrared heat-seeking surveillance planes, they’d turned up nothing.

“It’s like your friend just vanished from the face of the earth,” a Gila Park volunteer told me. “This is the most intense search I’ve ever seen, and we’re not getting anything. Not even a scent.” While we were being briefed, one of the search directors paused to stare at my feet. I’d only planned to be in L.A. for two days, so the only shoes I had were a pair of Barefoot Ted’s huaraches. “Ok, I’m not allowed to see those,” he said. “You should get going before I do.”

We grabbed light backpacks and water bottles and were assigned to a team. Two SAR veterans from Roswell, New Mexico took me, Luis, and Patrick Sweeney, a California runner who’d made the drive down with us. Kyle Skaggs was already out with a team that included Nick and Jamil Coury, two trailrunning brothers from Arizona who have gone to Caballo’s race every year since 2009. Our two teams would start from opposite directions and criss-cross in the middle, so we’d cover the same 10-mile loop twice and from both sides. We began scrabbling through gullies and juniper brush, hollering and yodeling as we climbed toward a mesa at 8,000 feet.

“CABAAAY-YOOOOEEE.....

“MICAH TRUUUUUUUEEEE....

“Ca-BAAAAA-YOOO, you pain in the aaaaaaasssss! Where the hell are you?”

Now that fast legs like Skaggs and the Courys were on his trail, we were sure we’d find Caballo by dark. When we didn’t, when we were trudging back defeated that evening, we were so baffled and dispirited that weird speculation didn’t sound so weird anymore. Scott Jurek began wondering if a drug cartel had contracted a hit on Caballo, planning it for his home turf to avoid detection. Barefoot Ted left me a message hinting that maybe it was no accident; after all, Gila was Geronimo’s hideaway and Caballo always said he wanted to end his days Apache-style with one final walk into the wilderness. Someone I’d never met emailed to remind me of the opening epigram in Born to Run: “The best runner leaves no trace.”

Yeah, right; Luis wanted action, not melodrama. As soon as we reached base, he went in to the search director. “Look, you’ve got some of the best trail runners in the country right outside your door,” he said. “They’re an unbelievable resource. You ought to hear what they have to say.” To his tremendous credit, the director grabbed a clipboard and was soon standing in a circle of ultrarunners, fielding suggestions.

“Did you take Caballo’s dog out?” Luis asked.

“Yes.”

“Did you walk him, or run him?”

“We walked him. He got a scent, but it turned out he was tracking a deer.”

“That’s because you walked him,” Luis said. “Dogs behave differently when they’re running. They’re moving too fast to get distracted. If he’s running, out of habit he’ll go where Daddy went.”

“Ok,” the search director said. “So how far could Micah go?”“He had huge range,” Luis said. “If he felt like it, he could turn 12 miles into 30.”

So instead of walking a grid where Caballo might be, why not let us run the trails where he had to be? The Gila is so steep and scrabbly, Kyle and Scott could cover more ground in a day than a horse. The search director promised he’d think it over, but by the next morning, Luis and Kyle had come up with plans of their own. It was Saturday, and more of Caballo’s friends and fans had arrived, bringing the number of volunteers at the pre-search briefing up to about 50. Simon Donato, a Canadian geologist who’d helped search for missing balloonist Steve Fosset, had come in from Calgary; with him were Caleb Wilson and Tim Pitts, two fellow ultrarunners he’d met at Caballo’s race.

With that many searchers, Luis figured we could slip away without being noticed. He wanted to go back to the lodge, put a leash on Guadajuko, and do his best to mimic Caballo’s running style to see where Guadajuko would lead him. Meanwhile, Kyle motioned for Scott Jurek and I to quietly follow him.

“They might ban us from the search after this,” Scott pointed out.

“It’s Day 5,” Kyle said. It was below freezing at night and scorching by day. Without warmth or water, Caballo might not have a Day 6.

Just before we sidled off, a hand grabbed my shoulder. It was Peter Sarsgaard, the actor who first read about Caballo on the set of “The Green Lantern” and was named to direct the Born to Run movie. Sarsgaard had only met Caballo once, back when he’d asked for help with the film and Caballo said he wasn’t really interested if he couldn’t play himself. Despite that, and the fact that his wife, actress Maggie Gyllenhaal, was due to give birth any day, Sarsgaard had flown down to Albuquerque from New York and started driving at 3 a.m. so he could make it to Gila before the search began. Due in no small part to Caballo’s example, Sarsgaard has turned himself from a smoker and non-runner into a ferocious and somewhat Caballo-esque dirt demon; he’s whipped me on my home trail, and when he got lost once during an 8-mile run in Italy, he kept going and ran a full marathon instead.

The four of us set off on a 20-mile loop that would climb Little Bear Canyon and circle back down along the river. Kyle could only envision two scenarios: either Caballo had taken a hard fall while heading for water, or he’d mis-stepped on a switchback and gone over the cliffs. Nothing else made sense. We started at a fast hike, then broke into a run, splitting into two-man teams whenever the trail forked, finding each other and re-grouping with hollers and whistles.

By noon, we’d gone double the distance of Caballo’s turnaround point and hadn’t seen a thing: not a footprint, not a blood smear, not even a hidden trail or gully. We’d been going hard on a hot day, climbing steadily till we’d hit 8,000 feet, so we stopped to cool down and water up. We passed around bags of dates and nuts, resting in the thin shade of scrub junipers. We checked the sky, but no help there; it was too early in the spring for buzzards. Scott took a look at my feet. By sheer luck, an SAR volunteer from Albuquerque had turned up with an extra pair of Brooks Cascadias in my none-too-common size 13, allowing me to swap out from Barefoot Ted’s huaraches. Scott helped design the Cascadias, and we began chatting about how they compared to the new wave of barely-there trail shoes.

Looking back, that’s when I knew the search was over. We didn’t ease up—we soon got back on the trail and kept beating the brush until daylight faded—but the adrenaline charge which had kept us hammering for three days had been subtly re-channeled from urgency into potency. No one said it, but we’d begun to enjoy the run, to the point where it felt less like a rescue and more like a tribute. I kept catching myself thinking, “I never would have known these guys without Caballo. I never would have even attempted a run like this before I met him.” We’d lost Caballo — we could feel it — but the Caballo-feeling was taking over.

SIMON DONATO AND HIS FRIENDS must have felt it as well, because that evening, they did exactly what Caballo would have done. They’d finished their search assignment and it was getting dark, so the only smart play was to get into their sleeping bags, rest up, and avoid getting lost themselves. But since Caballo had to be somewhere north — dead certain, no doubt about it — they went back out and headed south. Soon, they ran into Ray Molina, who’d known Caballo longer than any of us. Ray and his partners had gone even further in the wrong direction... and there, looking so peaceful, was Caballo, lying along the banks of a creek with his legs still in the water. Ray had immediately screamed “MICAH” thinking he could wake him up, but by then it was too late.

They built a fire, and spent one final night out in the wild with their friend. By early morning, SAR was able to get a horse — a white one — down into the canyon to carry Caballo’s body out. His hands and knees were scuffed, making it appear he’d taken a fall while following the creek out of the woods. Donato wants people to know that.“The creek would have led him back,” Donato said. “He knew what he was doing.”

As of today, the coroner hasn’t discovered what killed Caballo. The most credible theory I’ve heard is Chagas disease, a tropical parasitic infection that gradually weakens the heart. Caballo had told me about weird fainting spells he’d had over the years, and not long ago he’d felt so listless and feverish that he thought he’d contracted West Nile. Both symptoms could indicate Chagas. But just writing those words makes me feel pompous and stupid, because it’s exactly the kind of thing that would make that cut-the-crap grin creep across Caballo’s face.

“McOso, who cares how Geronimo died?” he’d say. “Let's just talk about how he lived.”