A fixture in Native American culture, sweat lodges were embraced by men's groups in the sixties and again in the nineties as macho bonding experiences, hearty cures for the emasculating upheaval of the women's-liberation and political-correctness movements. Today they're mostly seen as dangerous. In February, James Arthur Ray—onetime guest of Oprah Winfrey and the founder of a self-help empire once worth roughly $10 million—was indicted for manslaughter. Four months earlier, he had presided over a sweat-lodge ceremony in Sedona, Arizona, in which three people died, including a 38-year-old female surfing and hiking buff and a 40-year-old male business-development director for an Internet marketing company. Sixteen more were hospitalized for dehydration, burns, respiratory problems, and kidney failure.

The guys in Pasadena are well aware of the story, but they are by no means troubled by it. "I want to see what my body can take," says Jesse Garcia, an actor who starred in Pee-wee Herman's recent comeback show. Without question, the bravado that comes with giving the experience a try is part of the sweat lodge's appeal. "I like to tell the other dads at my kid's hoity-toity school, 'Hey, man, I did a sweat this weekend,'" says 49-year-old former TV producer Brian Wry. But for guys who are feeling overworked and undercompensated, guys whose careers and lifestyles have been curtailed by the recession, the challenge is the draw. Think of it as the Red Bull approach to therapy. It's quick. It's extreme. And it lets you do all the driving.

"We're trying to get you back to a place where you feel like things are just beginning," says Erin Kirk, the shaman who will lead the Pasadena men on their rugged trek through the spirit world. "We're all trying to wake up a little. We're on too many drugs, too many painkillers. We've just become robots."

What's the best way to fix that? Get the blood flowing. Push your body to its limits. Sweat-lodge sessions are divided into four rounds of prayers and songs; before each one the tent flap is unsealed and red-hot volcanic rocks are placed into the fire pit. The volume of water that gets dumped on them determines how intense things become. The temperature inside the lodge can range from 120 to 200 degrees.

"There's an aspect of suffering," says Kishan Shah, 35, a Venice Beach yoga teacher who has been visiting sweat lodges for six years, "but it allows you to break down preset boundaries about yourself. You get to take a good look inside. But you have to remain focused or you can become overwhelmed. I've had it happen where my mind was telling me 'You're going to die.'"

In the extreme heat, some guys find that their minds open as much as their pores. "These things provide men a setting to explore who they are, because they don't feel as comfortable in the rest of their lives," says Jonathan Ellerby, the author of Return to the Sacred, a book about spiritual practices. "Men who you think wouldn't shed a tear do."

This is Kim's fourth trip to a sweat lodge. He was drawn to the experience, he says, because he thought it would help him flush out toxins in much the same manner as the Russian baths he used to visit in New York City to recover from his hangovers. Before an earlier lodge experience, he poked fun at the supernatural stuff, joking with Kirk about finding his "spirit animal." He'd just returned from a trip filled with wildlife sightings in Alaska. During the final round of prayers, as Kirk thanked the spirits, an image of a fox—an animal he'd seen while touring the Denali National Park—flashed in his mind. "It made me more of a believer," he says. Enough of a believer to adopt the name Summer Fox in the lodge—as in "Great Spirit, it's Summer Fox."