CLEARWATER, Fla. — Raised as Scientologists, Christie King Collbran and her husband, Chris, were recruited as teenagers to work for the elite corps of staff members who keep the Church of Scientology running, known as the Sea Organization, or Sea Org.

They signed a contract for a billion years — in keeping with the church’s belief that Scientologists are immortal. They worked seven days a week, often on little sleep, for sporadic paychecks of $50 a week, at most.

But after 13 years and growing disillusionment, the Collbrans decided to leave the Sea Org, setting off on a Kafkaesque journey that they said required them to sign false confessions about their personal lives and their work, pay the church thousands of dollars it said they owed for courses and counseling, and accept the consequences as their parents, siblings and friends who are church members cut off all communication with them.

“Why did we work so hard for this organization,” Ms. Collbran said, “and why did it feel so wrong in the end? We just didn’t understand.”

They soon discovered others who felt the same. Searching for Web sites about Scientology that are not sponsored by the church (an activity prohibited when they were in the Sea Org), they discovered that hundreds of other Scientologists were also defecting — including high-ranking executives who had served for decades.

Fifty-six years after its founding by the science fiction writer L. Ron Hubbard, who died in 1986, the church is fighting off calls by former members for a Reformation. The defectors say Sea Org members were repeatedly beaten by the church’s chairman, David Miscavige, often during planning meetings; pressured to have abortions; forced to work without sleep on little pay; and held incommunicado if they wanted to leave. The church says the defectors are lying.

The defectors say that the average Scientology member, known in the church as a public, is largely unaware of the abusive environment experienced by staff members. The church works hard to cultivate public members — especially celebrities like Tom Cruise, John Travolta and Nancy Cartwright (the voice of the cartoon scoundrel Bart Simpson) — whose money keeps it running.

But recently even some celebrities have begun to abandon the church, the most prominent of whom is the director and screenwriter Paul Haggis, who won Oscars for “Million Dollar Baby” and “Crash.” Mr. Haggis had been a member for 35 years. His resignation letter, leaked to a defectors’ Web site, recounted his indignation as he came to believe that the defectors’ accusations must be true.

“These were not the claims made by ‘outsiders’ looking to dig up dirt against us,” Mr. Haggis wrote. “These accusations were made by top international executives who had devoted most of their lives to the church.”

The church has responded to the bad publicity by denying the accusations and calling attention to a worldwide building campaign that showcases its wealth and industriousness. Last year, it built or renovated opulent Scientology churches, which it calls Ideal Orgs, in Rome; Malmo, Sweden; Dallas; Nashville; and Washington. And at its base here on the Gulf Coast of Florida, it continued buying hotels and office buildings (54 in all) and constructing a 380,000-square-foot mecca that looks like a convention center.

“This is a representation of our success,” said the church’s spokesman, Tommy Davis, showing off the building’s cavernous atrium, still to be clad in Italian marble, at the climax of a daylong tour of the church’s Clearwater empire. “This is a result of our expansion. It’s pinch-yourself material.”

As for the defectors, Mr. Davis called them “apostates” and said that contrary to their claims of having left the church in protest, they were expelled.

“And since they’re removed, the church is expanding like never before,” said Mr. Davis, a second-generation Scientologist whose mother is the actress Anne Archer. “And what we see here is evidence of the fact that we’re definitely better off without them.”

‘Bridge to Total Freedom’

Scientology is an esoteric religion in which the faith is revealed gradually to those who invest their time and money to master Mr. Hubbard’s teachings. Scientologists believe that human beings are impeded by negative memories from past lives, and that by applying Mr. Hubbard’s “technology,” they can reach a state known as clear.

They may spend hundreds of hours in one-on-one “auditing” sessions, holding the slim silver-colored handles of an e-meter while an auditor asks them questions and takes notes on what they say and on the e-meter’s readings.

By doing enough auditing, taking courses and studying Mr. Hubbard’s books and lectures — for which some Scientologists say they have paid as much as $1 million — Scientologists believe that they can proceed up the “bridge to total freedom” and live to their full abilities as Operating Thetans, pure spirits. They do believe in God, or a Supreme Being that is associated with infinite potential.

Ms. Collbran, who is 33, said she loved the church so much that she never thought she would leave. Her parents were dedicated church members in Los Angeles, and she attended full-time Scientology schools for several years. When she was 8 or 9, she took the basic communications course, which teaches techniques for persuasive public speaking and improving self-confidence and has served as a major recruiting tool.

By 10, Ms. Collbran had completed the Purification Rundown, a regimen that involves taking vitamins and sitting in a sauna (a fixture inside every Scientology church) for as much as five hours a day, for weeks at a time, to cleanse the body of toxins.

By 16, she was recruited into the Sea Org, so named because it once operated from ships, wearing a Navy-like uniform with epaulets on the shoulders for work. She fully believed in the mission: to “clear the planet” of negative influences by bringing Scientology to its inhabitants. Her mindset then, Ms. Collbran said, was: “This planet needs our help, and people are suffering. And we have the answers.”

Christie and Chris Collbran were married in a simple ceremony at the Scientology center in Manhattan. Although she and her parents were very close, she said they had spent so much to advance up the bridge that they could not afford to attend the wedding.

It was in Johannesburg, where the couple had gone to supervise the building of a new Scientology organization, that Mr. Collbran, who is 29, began to have doubts. He had spent months at church headquarters in Clearwater revising the design for the Johannesburg site to meet Mr. Miscavige’s demands.

Mr. Collbran said he saw an officer hit a subordinate, and soon found that the atmosphere of supervision through intimidation was affecting him. He acknowledges that he pushed a 17-year-old staff member against a wall and yelled at his wife, who was his deputy.

In Johannesburg, officials made the church look busy for publicity photographs by filling it with Sea Org members, the Collbrans said. To make their numbers look good for headquarters, South African parishioners took their maids and gardeners to church.

But the Ideal Orgs are supposed to be self-supporting, and the Johannesburg church was generating only enough to pay each of the Collbrans $17 a week, Mr. Collbran said.

“It was all built on lies,” Mr. Collbran said. “We’re working 16 hours a day trying to save the planet, and the church is shrinking.”

‘It’s Everything You Know’

The church is vague about its membership numbers. In 11 hours with a reporter over two days, Mr. Davis, the church’s spokesman, gave the numbers of Sea Org members (8,000), of Scientologists in the Tampa-Clearwater area (12,000) and of L. Ron Hubbard’s books printed in the last two and a half years (67 million). But asked about the church’s membership, Mr. Davis said, “I couldn’t tell you an exact figure, but it’s certainly, it’s most definitely in the millions in the U.S. and millions abroad.”

He said he did not know how to account for the findings in the American Religious Identification Survey that the number of Scientologists in the United States fell from 55,000 in 2001 to 25,000 in 2008.

Marty Rathbun, who was once Mr. Miscavige’s top lieutenant, is now one of the church’s top detractors. The churches used to be busy places where members socialized and invited curious visitors to give Scientology a try, he said, but now the church is installing touch-screen displays so it can introduce visitors to Scientology with little need for Scientologists on site.

“That’s the difference between the old Scientology and the new: the brave new Scientology is all these beautiful buildings and real estate and no people,” said Mr. Rathbun, who is among several former top executives quoted by The St. Petersburg Times in a series of articles last year about the church’s reported mistreatment of staff members.

When Mr. Collbran decided he wanted to leave the Sea Org, he was sent to Los Angeles, where potential defectors are assigned to do menial labor while they reconsider their decision. Ms. Collbran remained in Johannesburg, and for three months the church refused to allow them to contact each other, the Collbrans said.

Letters they wrote to each other were intercepted, they said. Finally, Ms. Collbran was permitted to go to Los Angeles, but husband and wife were kept separated for another three months, the Collbrans said, while they went through hours of special auditing sessions called “confessionals.” The auditors tried to talk them out of leaving, and the Collbrans wavered.

They could not just up and go. For one, they said, the church had taken their passports. But even more important, they knew that if they left the Sea Org without going through the church’s official exit process, they would be declared “suppressive persons” — antisocial enemies of Scientology. They would lose the possibility of living for eternity. Their parents, siblings and friends who are Scientologists would have to disconnect completely from them, or risk being declared suppressive themselves.

“You’re in fear,” Mr. Collbran said. “You’re so into it, it’s everything you know: your family, your eternity.”

Mike Rinder, who for more than 20 years was the church’s spokesman, said the disconnect policy originated as Mr. Hubbard’s prescription for how to deal with an abusive spouse or boss.

Now, “disconnection has become a way of controlling people,” said Mr. Rinder, who says his mother, sister, brother, daughter and son disconnected from him after he left the church. “It is very, very prevalent.”

Mr. Davis, the church’s current spokesman, said Scientologists are no different from Mormons, Catholics, Jehovah’s Witnesses and Amish who practice shunning or excommunication.

“These are common religious tenets,” he said. “The very survival of a religion is contingent on its protecting itself.”

The Collbrans went back to work for the church in Los Angeles, but Ms. Collbran found the atmosphere so oppressive, the staff members so miserable, that she likened it to living under “martial law” and again resolved to leave.

So she intentionally conceived a child. She knew that the Sea Org did not allow its members to have children, and she had known women who were removed when they refused to have abortions. She waited until her pregnancy had almost reached the end of the first trimester to inform her superiors. It still took two months before the church let the Collbrans go, in 2006, and not before making them sign affidavits.

“All of the auditing that you do, there’s files kept on it,” Ms. Collbran said. “All of the personal things you ever said, all the secrets, the transgressions, are all kept in there. They went through that file, wrote this affidavit as if I wrote it — and I never wrote this affidavit, the church wrote it — and made me sign it.”

They were also handed what the church calls a “freeloader bill” for services rendered, of $90,000, which they later negotiated down to $10,000 for Ms. Collbran’s portion and paid. They now had a child and no money, but they thought they were still in good standing with their church.

Mr. Davis, the church spokesman, said the Collbrans’ exit was not unusual. The Sea Org is a religious order that requires enormous dedication, he said, and leaving any religious order can be a lengthy process. He said the church does require departing staff members to pay freeloader bills and to sign affidavits drawn up by church officials, but he contends that the affidavits never contain confidential information drawn from auditing sessions.

“We have never violated that trust,” Mr. Davis said. “We never have. We never will.” The church in Johannesburg is thriving now that the Collbrans have left, Mr. Davis said.

‘Suppressive Persons’

In 2008, organizers with the Internet-based group Anonymous began waves of protests outside Scientology churches in many countries. Anonymous said it was protesting the Church of Scientology’s attempts to censor Internet posts of material the church considered proprietary — including a video of Tom Cruise, an ardent Scientologist, that was created for a church event but was leaked and posted on YouTube.

“Since Anonymous has come forward,” said Marc Headley, who belonged to the Sea Org for 16 years, “more and more people who have been abused or assaulted are feeling more confident that they can speak out and not have any retaliation happen.”

Mr. Headley, who wrote a book about his experiences, is suing the church for back wages, saying that over 15 years his salary averaged out to 39 cents an hour. His wife, who said the church coerced her into having two abortions, has also filed a suit. The couple now have two small children.

The church acknowledges that Sea Org members are not allowed to have babies, but denies that it pressures people into having abortions. On the pay issue, it says that Sea Org members expect to sacrifice their material well-being to devote their lives to the church.

Scientology parishioners interviewed in Clearwater seemed unperturbed by the protests, headlines and lawsuits.

Joanie Sigal is a 36-year parishioner in Clearwater who promotes the church’s antidrug campaign to local officials. She said the defectors’ stories were like what you would hear “if I asked your ex-husband what he thought of you.”

“It’s so not news,” she said. “It’s a big yawn, actually.”

The Collbrans, despite their efforts to remain in good standing in the church, were declared suppressive persons last year. The church discovered that Mr. Collbran had traveled to Texas to talk with Mr. Rathbun, the defector who runs a Web site that has become an online community for what he calls “independent Scientologists.”

The church immediately sent emissaries to Ms. Collbran’s parents’ house in Los Angeles to inform them that their daughter was “suppressive,” Ms. Collbran said. They have refused to speak to her ever since. Recently, Ms. Collbran received an e-mail message from her mother calling her a “snake in the grass.”

Ms. Collbran says she still believes in Scientology — not in the church as it is now constituted, but in its teachings. She still gets auditing, from other Scientologists who have defected, like Mr. Rathbun.

Mr. Davis said there is no such thing: “One can’t be a Scientologist and not be part of the church.”

Mr. Collbran, for his part, wants nothing to do with his former church. “Eventually I realized I was part of a con,” he said, “and I have to leave it and get on with my life.”

Despite all they have been through together, Ms. and Mr. Collbran are getting a divorce. The reason, they agree sadly, is that they no longer see eye to eye on Scientology.