Here’s a piece of insider information from my corner of the yoga world: we yogis rarely say, “He is really good at yoga.” Instead we would say that the person “has a beautiful practice” or, perhaps, “her practice is deep.” It may seem overly flowery or needlessly vague, but such a distinction reflects the non-competitive spirit of most yoga traditions.

So it was with some skepticism that I began reading Hell-Bent: Obsession, Pain, and the Search for Something Like Transcendence in Competitive Yoga. Author Benjamin Lorr clearly knows his audience, however, and makes an excellent case for open-mindedness before leading us into the inspiring, if slightly scary, world of Bikram yoga. “Yoga is simply one of those things impervious to certainty, as incapable of corruption as it is of authenticity. And no amount of bossy, possessive attempts to claim a ‘real yoga’ will make it otherwise.” Point taken.

I admit that I’ve never set foot in a Bikram hot room. I tend to trust that the body does quite well when allowed to heat itself, from the inside out. But Hell-Bent has left me more than a little intrigued, and I know I will give it a try, sooner rather than later. Lorr’s account convinced me that there is something to this brand (literally, brand) of yoga, and so I will test myself against the heat.

Make no mistake, however: although the name is not in the subtitle, this book is both an homage to and an exposé of Bikram yoga, the tradition founded by Bikram Choudhury and famously practiced in super-heated rooms. Lorr used Bikram yoga to transform himself from an overweight guy to a national yoga competitor. Still more impressive are the myriad other case studies he weaves into his narrative. Lorr’s longtime friend Sol, obese and post-gall bladder surgery, suffers the hot room, loses the weight, and develops a practice so deep that Lorr fails to recognize him on the next mat. And then there was Joseph, whose childhood included diagnoses of pediatric rheumatoid arthritis and variant angina — the latter diagnosed after a heart attack at age 13 — overcame the pain, depression and disability in the hot room and went on to win the 2011 International Yoga Asana Championship.

Hell-Bent has no shortage of astonishing tales of transformation through the discipline of Bikram yoga. These shining examples start to tarnish slightly, however, as Lorr begins to reveal the man behind the curtain.

Bikram Choudhury brought his unique style of yoga to the U.S. during the Nixon administration. Now, according to Lorr’s account, there are 1.1 million Bikram practitioners in this country alone; 1,700 studios around the world; and more than 8,000 instructors certified by Choudhury to teach his 26-posture series.

Although he began training at age 5 and eventually became a champion yogi in his native India, Bikram is best-known, in the yoga world and beyond, for his eccentricities, flamboyant dress, tremendous wealth and ostentation. He is known also for his passionate mission to make yoga an Olympic event. Lorr’s experiences and interviews show a darker side to the man.

During the grueling 9-week residential training program for aspiring teachers, Lorr spent many hours with Bikram himself and his most senior teachers and devoted students. The training process he describes calls to mind boot camp, involving hours of practice in blistering heat and rote memorization of the instructor’s script, seasoned liberally with sleep deprivation, bad food, and rampant illness. More distressing still are the descriptions of Bikram’s ranting and harassment of his student teachers, each of whom has paid $11,000 for the training. One student who incurred his wrath was dubbed “Ms. Boobs,” and from then on endured an astonishing amount of humiliation. Another, Brian, reported being denied his certification because he had previously attended classes at a faux-Bikram studio. In a particularly vivid display of greed coupled with cruelty, Bikram had planned from the outset to withhold Brian’s teaching credentials (and any refund of the training fees), yet allowed him to endure the nine-week training before informing him of his transgression.

Hell-Bent is populated with people like Brian, with women who recount Bikram’s sexual advances and harassment, and with long-devoted students and teachers — Esak, Tony, Chad — exiled from the Bikram community when some mistake threatened their guru’s place at the center of the universe. And yet, the man himself seems unscathed by fallout from his own scandalous behavior.

“Bikram is still right there today, teaching class himself, on a dais in his headquarters in Beverly Hills: hips wrapped tight in a leopard print, chest freshly waxed, demanding perfection through his headset microphone to a room of hundreds, smiling as his students compete to feel pain in front of him.”

The unanswered question at the heart of Lorr’s fascinating account is why? Why has no one demanded better behavior from this man? Why do even the most wounded seem (pardon me) hell-bent on returning to his good graces? What is it about this man that has allowed him to remain atop his sequin-encrusted pedestal? There is certainly precedent in the yoga world for toppling gurus gone astray. In the 1990s, Amrit Desai, founder of Kripalu yoga, confessed to having sex with students and subsequently resigned his leadership of the Kripalu community. Much more recently, the world of Anusara yoga was rocked by a similar scandal involving its charismatic founder, John Friend.

What compels these gurus toward shockingly bad behavior, sullying the reputations of the wonderful systems of yoga they created? And why does Bikram Choudhury escape consequences? Hell-Bent will fascinate the reader, but leave that question for each of us to ponder.

Susan Young is a yoga teacher and health writer. She lives with her family in Montgomery Village, Md.