The gaunt, bearded man in a white smock and large sombrero at the Plaza Santa Maria, a Mexican health spa of slim medical reputation, was known by the alias "Don Schoonover," but there was no disguising the seriousness of his illness. He had mesothelioma, a rare form of lung cancer, possibly linked to asbestos inhalation, that usually strikes middle-aged men and is generally regarded as fatal. Last week the man was identified as actor Steve McQueen, 50. The news was shocking, but so were the questions raised about McQueen's treatment and the unorthodox healer behind it.

Symptoms first appeared late last year. After an unusually exhausting shoot on his last movie, The Hunter, McQueen checked into L.A.'s Cedars-Sinai Medical Center where doctors discovered the disease. Mesothelioma is characterized by weight loss, accumulation of fluid, nausea and severe pain. The disease is considered inoperable and untreatable by chemotherapy or radiation. McQueen reportedly was told his case was terminal.

Six months ago he secretly met in remote Winthrop, Wash, with William Donald Kelley (following story), a controversial Texas orthodontist who had developed a "holistic medicine" cancer treatment. Says Kelley, "There are no recoveries from Steve's form of cancer in the medical literature—if he recovers, we'll be breaking new ground."

Last April Kelley contracted with Plaza Santa Maria, which only 18 months earlier had been an oceanside tourist resort, to treat patients with his unusual methods. The spa's chairman, Rodolfo Alvarez, is a cosmetics and pharmaceuticals importer-exporter. Though now treating 40 or so victims of degenerative diseases, the spa reportedly has no lab, no X-ray equipment, no clinical facilities. Directly supervising McQueen's treatment is Dr. Rodrigo Rodriguez, 36, an M.D. with a postgraduate degree in nuclear medicine from the University of Mexico. He previously worked in a Tijuana laetrile clinic. Dr. Rodriguez claims, "I have seen cases of complete remission of mesothelioma at the Plaza Santa Maria and other hospitals in Mexico."

McQueen checked into the Plaza on July 31. "He walked to his room," says an eyewitness, "but he was ambulatory more from sheer guts than physical ability." At first he was given up to 30 grains of codeine a day, as well as laetrile, the FDA-banned cancer drug extracted from apricot pits. "But not now," says Dr. Rodriguez. "Our program is meant to build up the immune system." Individual treatment is determined by computer on the basis of a patient's answers to Kelley's 2,500-item questionnaire. McQueen's responses have put him on a daily regimen of saunas and enemas, chiropractic manipulation and massages, exercises and drugs, like marujama, a Japanese extract of tuberculosis bacilli Z. The actor follows a "metabolic nutrition" diet involving more than 100 vitamin and mineral pills daily, enzyme injections and, says Dr. Rodriguez, "freshly squeezed juice from organically grown fruit and vegetables, raw certified milk and foods you would describe as 'health foods.' " To supplement this diet, McQueen has friends sneak in Häagen-Dazs brand ice cream.

Dr. Rodriguez claims McQueen has "shown no new tumor growth, shows clear shrinkage of existing tumors, and has a much better appetite." Chimes in spa chairman Alvarez, "He weighs more than me, and I weigh 129 pounds." Dr. Rodriguez attributes part of McQueen's "improved mood and outlook" to Barbara Minty, 26, McQueen's wife of nine months, who "has been very helpful. We do not take patients by themselves. The companion lives with the patient, eating what he eats, doing what he does. She holds Steve's hand and does things like bring him his tray and dishes." Barbara and Steve reportedly pray together in their villa. Raised as a Catholic, he now feels he has, according to one friend, "made his peace with God."

Rodriguez says McQueen has walked around the grounds and even swum in the Plaza's pool. He has been reading the Collins-LaPierre best-seller The Fifth Horseman and screening movie cassettes on his video machine. (He donated a complete set of his own movies to the spa.) With courage and a great will to live, McQueen himself apparently feels he is getting better. In a taped message broadcast on Mexican radio last week, the actor said, "Mexico is showing the world a new way of fighting cancer through nonspecific metabolic therapies. Thank you for helping to save my life."