June 8, 2012 -- An Arizona man who was a member of a Buddhist yoga retreat that his family compared to a cult was found dead in a mountain cave in Bowie, Ariz., Tuesday, weeks after being asked to leave the sect with his wife.
When rescuers found 38-year-old Ian Thorson, he was dead, apparently from exposure and dehydration, and his wife, Christie McNally, 39, was delirious.
The two were followers of the controversial spiritual leader Michael Roach, a Princeton-educated Buddhist monk, and they had entered a mysterious descent into darkness in recent weeks that would change their lives forever. In Dec. 2010, Thorson, McNally and about 35 other people hugged their families goodbye and entered into a three-year silent meditation retreat. Thorson's family never saw him alive again.
This strange story starts more than a decade ago when Thorson, then a recent Stanford graduate, found his way into the orbit of the charismatic Roach, who made millions in the diamond business and then became a Buddhist monk.
Thorson's mother Kay and his sister Alexandra said they were immediately suspicious of Roach. Kay Thorson said she believes Roach's group is a cult and that he promised her son "enlightenment in one lifetime," asking for "total dedication" in return.
"He always seemed a little creepy to me," said Alexandra Thorson.
Roach is a highly-trained monk in the same tradition of the Dalai Lama. However, in recent years, the Dalai Lama and other Buddhists have been very critical of Roach's decisions, such as living with women when he was supposed to be celibate, growing out his hair when monks traditionally shave their heads, and building a global following of adoring acolytes.
Under the sway of Michael Roach, Ian Thorson changed dramatically, losing weight and his spirit, his family said.
"He was not his person anymore," Kay Thorson said. "He was a very independent and deep, good thinker before and he was tending to follow the group think, which is what happens gradually in a cultic situation."
"I felt like I lost a brother," Alexandra Thorson said. "He was totally changed. Before he was a frat boy, he was a surfer, he was a partier, he had jobs, he was a student. His focus just changed, I guess, like even his hugs weren't hugs. They were like shells of hugs."
Thorson's family said they called in cult deprogrammers to work with Ian after he had been with Roach's group for several years, but he ultimately returned to Roach.
Then in 2010, Thorson married Christie McNally. It was a tricky romantic decision for him because McNally was formerly Roach's spiritual companion.
"There are so many women, why would you take that one?" Alexandra Thorson said of her brother's relationship with McNally. "That was not, in my opinion, a smart move."
McNally and Roach were profiled in the New York Times, talking about how they lived together in a yurt for years and were never more than 15 feet apart at all times. They said their relationship was platonic, but public records show they were married.
When McNally and Roach later split up, Roach was reported to have been distraught.
In her relationship with Thorson, McNally continued some aspects of the extreme intimacy she had shared with Roach. For starters, she and Thorson wrote a book together about partners yoga.
"Once we do this kind of yoga together, then the next day, when we try to do a series alone, it's really, really lonely," Ian Thorson said in a 2010 video posted on Youtube.
McNally was by his side. "It's really, really lonely, yeah," she said.
Thorson's sister said the pair was always at each other's side, and they would even share the same plate at meals and read books simultaneously.
"Reading the same book, slowly, same page, waiting, and then turning the page," Alexandra Thorson said. "I don't know if you could call it intimacy. It was almost invasive. They had no personal space."
In 2010, Ian Thorson and McNally went off for a retreat at Roach's "university" in the remote Arizona desert. After saying goodbye, they settled in for three years, three months and three days of silent meditation. However, after a year and a half, the couple was asked to leave.
According to a letter Michael Roach posted on his website, Thorson and McNally were the subject of a "mutual spousal abuse" investigation after a medical practitioner at the "university" allegedly treated Thorson for three stab wounds inflicted by McNally. The letter said McNally claimed it was an accident and it happened when she was playing with a knife.
After leaving, the couple went to live in a cave in the Arizona desert mountains close to Roach's group.
But six weeks later, McNally called 911, saying she had an emergency. When medical crews arrived, Thorson was dead. Police did not suspect foul play. An autopsy revealed that Thorson died of dehydration and exposure and there was no evidence of stabbings. Police are not conducting a criminal investigation.
"This is a very inhospitable environment," said Sgt. David Noland, the Search and Rescue coordinator for the Cochise County Sheriff's Office. "The Indians did it thousands of years ago, but I haven't heard of anybody living out off the land in this area."
Thorson's mother said she is still in shock over her son's death and that Michael Roach's allegations of spousal abuse are exaggerated. She and Thorson's sister believe his death would not have happened if Roach had not asked the couple to leave the retreat.
"Getting them geared up for this retreat and then kicking them off is setting them up for a problem," Alexandra Thorson said. "That was irresponsible, I felt."
On his website, Roach wrote that he took the appropriate precautions before sending the couple off, offering them money, an assistant and a rental car to ease their transition. He said they refused his help and refused to tell anyone where they were going. Roach also wrote that he is deeply sorry for the family's loss, but Thorson's mother said this case should be a wake-up call for parents about the dangers of extreme religious groups.
"There's nothing good that can come for me personally because my son is dead," Kay Thorson said. "I certainly don't want this to happen to someone else."
Roach declined to grant "Nightline" an interview. He is holding a seminar on reaching enlightenment this weekend.
ABC News' Lauren Effron contributed to this report