By Alex Tresniowski
May 08, 2006 12:00 PM

A typical day for Tammy DiNicola went something like this: wake up before dawn, jump off the hard board she slept on and into an ice-cold shower, whip her bare buttocks with a rope while praying, then slip a spiky metal band around her thigh and keep it there for two hours—all before breakfast. “I would think, ‘If this is what God wants me to do,'” says DiNicola, 38, “‘then I’m going to do it.'”

At the time, DiNicola was a member of Opus Dei, the Roman Catholic group depicted as the shadowy, murderous villains in the literary blockbuster The Da Vinci Code. The movie version—starring Tom Hanks and due May 19—only renews the controversy over Opus Dei, an organization known in the past for its secretiveness—and suspected of having friends in very high places. Tammy DiNicola left in 1990 after two years, claiming fellow members recruited too aggressively and tried to cut her off from her own family. Indeed, her parents have organized a network of disaffected former members.

The Opus Dei portrayed in Code is an even more extreme clique personified by Silas, an albino monk who whips himself bloody and slaughters people to protect Christianity’s alleged secrets. But that character, and the presentation of Opus Dei in general, “is completely outrageous and completely removed from reality,” says Brian Finnerty, the group’s American spokesman. He says that despite disgruntled former members like DiNicola, life in the group today is not nearly as gothic as some make it out to be. Opus Dei—Latin for “God’s work”—”is like a personal trainer for the spiritual life,” says Finnerty. “We try to give people extra help to come closer to God in their everyday lives.”

So is Opus Dei as sinister as a killer fanatic or as harmless as a personal trainer? Interviews with members and ex-members suggest the truth lies somewhere in between. Founded in 1928 by Josemaría Escrivá de Balaguer, a Catholic priest who believed people needed a way to be spiritual seven days a week, Opus Dei claims some 85,000 members around the world. In 1982, Pope John Paul II named the group a “personal prelature”—a sort of diocese without boundaries—conferring the Vatican’s approval.

“When you join Opus Dei you make a promise to God and say, ‘I want to deepen my relationship with you,'” says Fiorella Simoni de Cannon, 36, an environmental scientist from Arlington, Va. As one of the group’s so-called supernumeraries, she lives with her husband and says she has an otherwise ordinary life while adhering to practices like daily prayers, meditation and personal sacrifices (she takes stairs instead of elevators, for instance). She’s up early to pray or attend Mass, but some days she’s too busy to stick to all of her rituals. “When that happens, you miss the graces that come with them, but nobody asks, ‘Why weren’t you in church?'” she says. “Nobody knows because it’s so personal.”

That’s not quite true for a minority of hard-core members known as numeraries, who pledge to be celibate and live in Opus Dei houses. They pay no rent but hand over as much as 50 percent of their salaries and must ask for permission to leave the group. “We ask for the shirt off our members’ backs because people need to be more generous,” says a TV journalist who has been a member for 20 years and prefers to remain anonymous. The journalist practices mortification—wearing a spiky band called a cilice around his thigh and whipping himself with a lash called a discipline (see box). “They are slight irritations and small reminders of the suffering of Christ,” he says.

Still, that’s a far cry from the bloody, baroque world of The Da Vinci Code, which Fiorella Simoni de Cannon, for one, finds amusing. For her, joining Opus Dei was one of the best decisions of her life. “It just fits,” she says. “It feels like home. It’s God’s way of telling me, ‘This is the way I want you to be.'”