In another ET exclusive, our own Mark Steines is in Rome, Italy with none other than Oscar winners Tom Hanks, Ron Howard and Brian Grazer to investigate the incredible buzz behind 'Angels & Demons' -- the highly anticipated prequel to 'The Da Vinci Code'!

"I'm Tom Hanks -- check out our special sneak preview of 'Angels and Demons,'" the A-list star tells ET.

The film's producers chose only one show to visit the top-secret set, deep inside the Vatican City, where Hanks' Robert Langdon must confront a shadowy secret society, the Illuminati, to rescue four kidnapped cardinals and solve a conspiracy that may put the future of the Roman Catholic Church in peril.

The new movie has filmed at a variety of Roman locations found in the book, including the two-thousand-year-old Pantheon, the Church of Santa Maria della Vittoria, the Piazza Navona with its Fountain of the Four Rivers, the Castel Sant'Angelo and the centuries-old Biblioteca Angelica.

"Inside this Vatican library, a book by Galileo holds the clues to where the cardinals will be murdered," reveals Mark. "Now, those clues are hidden in what's called 'The Path of Illumination,' an elaborate kind of map that leads to the secret meeting place of The Illuminati.'

"This is a big day," says director Howard about the scenes lined up ahead. "We're accomplishing a lot and we're fortunate to be shooting in Rome, but it's logistically complicated."

"We've been making movies for 25 years and he e-mailed me the other day saying, 'This was one of the hardest working days of my life,'" says Grazer.

As for reuniting with Hanks for yet another big Hollywood project, Howard says, "It's fun. But meanwhile, we've worked together a long time; he's loose, a lot of laughs."

"He has a better hair 'do," jokes Grazer about Hanks' character, "and he's smarter and more relaxed."