Nicole Kidman was an open book in her new Vogue cover story with writer Jason Gay. The actress talked about the loss of her father, her past relationship with Tom Cruise and her current relationship with country singer Keith Urban. But One subject the Academy Award winner refused to talk about is Scientology and the HBO documentary, "Going Clear."

In the Vogue interview, Gay makes it very clear that the subject of Scientology is off limits and Kidman refused to discuss the subject. "Really the only topic Kidman declines to discuss is the Church of Scientology; the recent HBO documentary Going Clear alleged, among other things, that the church had actively tried to break up Cruise and Kidman's marriage," wrote Gay. "Kidman passed on the opportunity to speak to the makers of the film and has consistently turned away requests to comment out of respect for her children with Cruise."

In March, HBO released a documentary called "Going Clear: Scientology and the Prison of Belief," which alleged the Church of Scientology broke up Kidman's marriage with Cruise. The Church tapped her phone and was constantly tailed by private investigators, according to the film. Kidman also declined to be interviewed for the film.