'The Good Shepherd'

Dec. 15, 2006— -- Three giant stars…one big new movie. Robert De Niro, Angelina Jolie and Matt Damon have come together to make a film about America at the crossroads. "The Good Shepherd" tells the story of the men who created the CIA -- America's aristocrats embarking on an adventure that would forever change their lives and families.

All three stars sat down with ABC's Diane Sawyer to talk about their own adventures, lives, and families.

Jolie and Damon teamed up director Robert De Niro on his longtime passion project, a film about America's drift into the moral and spiritual shadows of the spy trade.

De Niro had been trying to get the film made for almost eight years, and told Sawyer that sometimes he wondered if it would ever happen.

"I still am amazed that it was done, because it's just so daunting," he said.

All three stars talked about how the world has changed in the past half century -- a humbling lesson for Americans with so many certainties about good and evil in the world.

"They were good shepherds," De Niro said. "Somebody told me that people do bad things in the name of good. So, everybody feels they're on the good side, the right side," he said.

Damon added that the movie takes place in a more "naive" time:

"They were incredibly powerful [people]. By the time the Bay of Pigs came up and they hadn't lost yet, you know? They must have felt on top of the world."

The film is also a kind of love story. Jolie plays Margaret, a rich girl with a wild side, who yields to convention and is crushed by a life of secrets.

"I always thought she was a ... a beautiful character, because you do see the potential of who she could have been," said Jolie.

Jolie also talked about how much she studied the women of that period, and what she learned about their lives.

"A woman at that time doesn't… speak in a way we do," she said. "She doesn't have the ability to feel that she can lash out, speak for themselves, think for themselves… I think early on we realized this was going to be the film where I am the weak victim and [Damon] is the cruel, cruel, terrifying, scary man."