New York -- The "it" book of the summer was "The Da Vinci Code." Chances are, if you haven't read it you know someone who did. But the book is turning into something much more than just a good summer's read.
CBS 2's Lisa Daniels reports that it's sparking a debate over the merits of a religious organization called "Opus Dei".
When Tammy DiNicolla looks the ritual whips she remembers the pain and blood from whipping herself, "They want you to do it so it hurts."
The whippings are rituals called "corporal mortification" associated with a Catholic organization called "Opus Dei".
"What you do is wrap it around your thigh so that the points stick into your thigh," says Tammy.
As a student at Boston College, Tammy didn't mind, she thought Opus Dei was wonderful, but her mother, Dianne, began to worry.
"As Tammy got further involved in Opus Dei she became stilted, withdrawn, the happy bubbly child disappeared," says Dianne.
After two and a half years of unsuccessful attempts to convince Tammy to leave Opus Dei, Dianne hired an interventionst to get her daughter back.
Now years later, Tammy believes she was brainwashed into believing salvation meant cutting all ties with her family and handing over her pay or face damnation.
"I look back, it's almost like I was a zombie," says Tammy.
It's a far cry from how Larchmont resident Cathy Hickey describes her experience with Opus Dei. "I knew I was looking for something more in my life and I found that this was a way to take my life with my family, the ordinary things that I do and find holiness there."
As a proud Opus Dei member for 25 years, Kathy, a devout Roman Catholic, says Opus Dei is really just an extension of the Catholic Church. "I would say that Opus Dei is at the heart of the church. It really embodies what Vatican 2 was all about."
There are facts to back up that claim, in 2002 Pope John Paul 2 made Opus Dei's founder, Father Josemaria Escriva, a Saint.
Even critics concede that Opus Dei is not a fringe organization. It currently boasts over 80,000 members around the world. Many of them are well-to-do professionals, and although its practices are famously shrouded in secrecy the church claims, through self-discipline and rigorous prayer, great social change can happen from small daily choices.
"It showed me my life is really important, that I can make something special of washing the dishes, of changing a diaper, of doing any of those things. It was so important in raising my children," adds Kathy.
This is why "The Da Vinci Code" is causing so much controversy. The book's plot centers around a fictional Opus Dei member who commits murder to cover up evidence that would destroy the Catholic faith.
"They feel they're portrayed as a James Bond villain, a kind of Dr. Evil which they are, to goose up the plot," says Professor Margaret Boe Birns of The New School.
Even more controversial is the the page entitled "Fact." Author Dan Brown writes: "Opus Dei is a deeply devout Catholic sect that has been the topic of recent controversy due to reports of brainwashing, coercion, and a dangerous practice known as corporal mortification."
The page was enough for Opus Dei to send a letter to Brown's publisher, Doubleday, demanding a retraction.
"Dangerous? Opus Dei is wonderful! Dangerous? It's almost laughable. It just puts you on the road to heaven, that's what it does," says Kathy.
But Tammy believes The Da Vinci Code shouldn't be laughed off. She says it exposes the truth about an organization she calls a cult, "They deceive and manipulate."
So the controversy continues. Opus Dei supporters on one side, critics on the other. In the meantime, an author with a bestseller that may stir more than just a good read.