She identified with concepts described in the book including the idea of attaining the Scientology state of clear, and became a member of the organization in 1969.

She hitchhiked from Chicago to Los Angeles, in order to begin the process of studying Scientology, and initially felt that it helped improve her life.

After being a member of the Scientology organization for ten years, Christman reached the spiritual Operating Thetan level of OT III, and learned the story of Xenu.

After serving in these roles, Christman came to work for the Office of Special Affairs (OSA), which functions as an intelligence agency within Scientology.

In 1999, OSA agents removed the censorship software "Scieno Sitter" from Christman's home computer, in order to allow her to carry out a mission of monitoring critical material about Scientology on the Internet.

Christman reported directly to OSA vice-president, Janet Weiland, about her efforts to remove criticism of Scientology from the media and online.

She supervised the Scientology Parishioners League, a group dedicated to removing criticism about the organization from the press, media, and Internet.

After an operation viewed as successful where Christman complained to MTV about a South Park parody involving Travolta and characters from the comedy series which satirized Scientology, she was assigned in 2000 to monitor postings to the newsgroup alt.religion.scientology.

[7] In recalling her initial thoughts upon reading the book by Hubbard, Christman commented, "I was really looking for a higher state of consciousness and a way of helping people.

[18] Her Sea Org career was short lived; she was instructed to cease taking prescribed medication for her epilepsy, and as a result experienced multiple serious seizures.

"[21] Christman recalled that her epilepsy was not recognized as a genuine medical condition by Scientology; whose practice was to instruct members to attempt self-treatment, specifically completing the Purification Rundown, a controversial detoxification program that utilizes saunas and vitamins.

After being a member of the Scientology organization for ten years, Christman reached the spiritual "Operating Thetan" level of OT III.

[16][17] She recounted her experience of reading the Xenu story upon reaching the level of OT III: "You've jumped through all these hoops just to get to it, and then you open that packet, and the first thing you think is, 'Come on.

[8] Christman spent time working at Narconon International,[24] a group affiliated with Scientology and promoted as a drug rehabilitation program using methods created by Hubbard.

[6] Christman assisted OSA agents in 1979, when a politician in Clearwater, Florida was attempting to hinder the Scientology organization's efforts to establish a presence in the city.

[6] She attended the court proceedings and wrote reports about members of the jury, and assisted Scientology lawyers in compiling profiles of the jurors.

"[6] In 1998, the Scientology organization publicized an initiative to hand out software on CDs to all its members, which would help them create their own websites describing their activity in the movement, and linking back to the main site at www.scientology.org.

[6] OSA agents wished for Christman to specifically monitor critical websites and report to the organization about her findings, so they removed the Scieno Sitter censorship software from the computer at her residence in 1999, allowing her to research sites online freely.

[6] She would receive instruction from OSA agents, and proceed to complain to journalists and television producers in an attempt to convince them to pull a critical segment on Scientology.

"[7] She was assigned to try to stop the MTV Movie Awards from featuring a South Park satire, which poked fun at Scientology and the film, based on a book by its founder L. Ron Hubbard, titled Battlefield Earth.

[6] In the eventual broadcast, which ran June 8, 2000, the South Park character Cartman was shown using a Scientology personality test as toilet paper.

[6] After the perceived success of her South Park assignment, OSA agents instructed Christman to deal with Scientology critics who congregated on the Internet.

[6] Christman identified with Heldal-Lund's ideals of free speech, and on July 20, 2000, she announced her intention to leave Scientology in a public post to ARS.

[6] She realized she would face repercussions from the organization for her actions, and asked Heldal-Lund for help; he recommended she contact a group of protesters against Scientology called the Lisa McPherson Trust (LMT) who were based in Clearwater.

[6] Through the Scientology practice of "disconnection", Christman's husband and the majority of her acquaintances and friends who were Scientologists at the time of her exit from the group excommunicated her and cut off contact.

[16][17] Christman recounted how after leaving the organization, the Church of Scientology attempted to damage her reputation through a policy referred to as "dead agenting".

[16][17] According to Christman, the Scientology organization publicized inaccurate information about her online, tried to get her removed from her position of employment, and filed a lawsuit related to her protesting against the group on church property.

[6] She maintained that the actions by representatives of Scientology against her were examples of the policy, "fair game"; a form of retribution for criticizing the organization.

[9] In his 2008 book Tom Cruise: An Unauthorized Biography, author Andrew Morton thanked Christman in the acknowledgements section for advising him with regard to the jargon and complicated history of Scientology.

[36][37] Her YouTube account was briefly shut down in April 2008 around the time period that the same thing happened to Mark Bunker; soon afterwards an unidentified individual posted to alt.religion.scientology and boasted of "silencing" Christman.