CANNES, France - Pregnant with twins, Angelina Jolie says the story behind her latest drama hits close to home: the loss of a child.

Jolie stars in Clint Eastwood's "Changeling," the true story of a Los Angeles woman who endured horrors at the hands of corrupt police in her crusade to find out what happened to her son after he vanished in 1928.

"To lose a child: I can't imagine anything worse, especially not knowing the fate of...