Today, the out-of-the-way 500-acre compound near Hemet has quietly grown into one of Scientology's major bases of operation, with thriving video and recording studios, elaborate offices and a multimillion-dollar mansion that former members say was built for the eventual return of "LRH," who died in 1986.
Scientology has long recruited Hollywood luminaries. But the close friendship of these two men for nearly 20 years and their mutual devotion to Hubbard help explain Cruise's transformation from just another celebrity adherent into the public face of the church.
The bond between the star and his spiritual leader was evident last year when the two traded effusive words and crisp salutes at a Scientology gala in England. Calling Cruise "the most dedicated Scientologist I know," Miscavige presented him with the church's first Freedom Medal of Valor.
"Thank you for your trust, thank you for your confidence in me," Cruise replied, according to Scientology's Impact magazine. "I have never met a more competent, a more intelligent, a more tolerant, a more compassionate being outside of what I have experienced from LRH. And I've met the leaders of leaders. I've met them all."
Founded in 1954, Scientology is a religion without a deity. It teaches that "spiritual release and freedom" from life's problems can be achieved through one-on-one counseling called auditing, during which members' responses are monitored on an "e-meter," similar to a polygraph. This process, along with a series of training courses, can cost Scientologists many tens of thousands of dollars.
As Scientology's highest-ranking figure, Miscavige, 45, has found in Cruise, 43, not just a fervent and famous believer but an effective messenger whose passion the church has harnessed to help fuel its worldwide growth.
"Across 90 nations, 5,000 people hear his word of Scientology — every hour," International Scientology News proclaimed last year. "Every minute of every hour someone reaches for LRH technology simply because they know Tom Cruise is a Scientologist."
Cruise and Miscavige declined requests for interviews.
A Scientology spokesman, Mike Rinder, called them the "best of friends," men who've achieved great success through "their force of personality and their drive to excel."
At the same time that Cruise's increasingly vocal advocacy of Scientology has drawn attention to his faith, it has collided with his career. While promoting "War of the Worlds" this year, the film's director, Steven Spielberg, grew concerned that Cruise was talking too little about the movie and too much about Scientology and his wide-eyed-in-love fiancee, Katie Holmes, who turns 27 today.
Their romance generated even more buzz when Holmes was seen in the nearly constant company of Jessica Rodriguez, who is from a prominent family of Scientologists. Holmes, who said after becoming engaged to Cruise that she was embracing Scientology, described Rodriguez as a close friend, though she was widely seen as a church-appointed companion.
Unlike Holmes' embrace of the church, Cruise's is not new. Long before he sprang onto Oprah's couch, jabbed an accusing finger at "Today" show co-anchor Matt Lauer and blasted Brooke Shields for taking antidepressants, Cruise undertook intensive Scientology study and counseling at the church's compound, according to current and former Scientologists.
The vast majority of Scientologists train at the church's better-known facilities, including those in Hollywood and Clearwater, Fla. Cruise also has trained at those locations, but for much of his studies in the late 1980s and early 1990s, he headed to Gilman Hot Springs.
He stayed for weeks at a time, arriving by car or helicopter, according to ex-Scientologists who saw him there on repeated occasions. The former resort, 90 miles east of Los Angeles, was an ideal place for Cruise to get out of the spotlight while focusing on his Scientology training, ex-members say.
Described by ex-members as the church's international nerve center, the property is largely concealed from outsiders by tall hedges and high walls. The complex's barbed-wired perimeter and driveways are monitored by video cameras, and motion sensors are placed around the property to detect intruders, ex-members say. Some also remember a perch high in the hills, dubbed "Eagle," where staffers with telescopes jotted down license plate numbers of any vehicle that lingered too long near the compound.
Behind the compound's guarded gates, Cruise had a personal supervisor to oversee his studies in a private course room, ex-members say. He was unique among celebrities in the amount of time he spent at the base. Others visited, they said, but only Cruise took up temporary residence.
"I was there for eight years and nobody stayed long at all, except for Tom Cruise and Nicole Kidman during that period," said Bruce Hines, who clashed with Miscavige and left Scientology in 2001 after three decades in the group.