Jan. 8, 2004 -- For nearly a decade, Charlize Theron has been one of Hollywood's certified goddesses, 5 feet 10 inches of traffic-stopping, red carpet-strutting, designer-clad glamour.

Roles in movies such as The Italian Job, Sweet November, Reindeer Games and The Cider House Rules put the actress on the A-list. She is getting rave reviews and a lot of Oscar buzz — and has even been nominated for a Golden Globe — for her bold, risk-taking performance as serial killer Aileen Wournos in her latest film, Monster.

That bravery also extends beyond her career. Theron spoke out in a public service announcement about the rarely talked-about rape crisis in her native South Africa. When the South African government got cold feet and pulled it, she went to court and fought to get it back on the air.

Theron says she got that kind of confidence from one person: her mother, Gerda. But the story is not one of a simple mother-daughter relationship.

Up until now, Theron has never told the story on television. "It's not just about me," she said. "If it was just about me, I think I could talk about it." She says her mother "has never asked to be in the spotlight, and she's never asked for any of this."

But on Primetime Thursday, Theron told the story to ABCNEWS' Diane Sawyer.

Fear of Firearms

It happened one night when Theron was 15 years old and had just returned home from boarding school. Her parents had a troubled marriage, but divorce was simply not an option among their friends in South Africa at that time.

"My dad was a big guy, tall, skinny legs, big belly," Theron told Sawyer. "[He] could be very serious but loved to laugh as well, and enjoyed life. He also had a disease. He was an alcoholic."

Theron says her father never physically abused her, but concedes "he was a verbal abuser."

On the night of June 21, 1991, Theron's father and his brother were returning home after a bout of drinking. An aunt called to warn of his agitation. "Nature gives you instinct. And I knew something bad was going to happen," Theron said.

When he arrived home, her father began shooting, first at the locked gate to the home, then through the kitchen door, according to her mother's later testimony. He began banging angrily on the door of Charlize's bedroom, saying, according to the testimony, "Tonight I'm going to kill you both with the shotgun."

"The terrible thing is that everybody in South Africa has a gun … You know, but that's just the lifestyle there. And those things are handy; terrible things happen," Theron said.

"You shouldn't have those things around because when people get irrational and emotional and drunk, terrible things can happen."

‘Those Are the Sacrifices’

After his threat, Theron's father fired his gun again — into her room. Her mother grabbed her own handgun and shot the two men, killing her husband and wounding his brother.

According to Theron's sworn statement to police, she asked her mom: "What happened?" The answer: "Charlize, I shot them … I shot them."

Her father was dead, but Theron says there was no doubt about her feelings about what her mother had done. "I know what happened," she said. "And I know that if my daughter was in the same situation, I would do the same thing."

But she admits she was also stunned. "I think, for me, it took a long time to sink in, what had really happened because you just don't think stuff like that will ever happen to you," she said. "You always think it happens to somebody else."

In the days following, Theron's devastated mother insisted that the teenager leave and resume her life away from home. Her mother said she would face the investigation on her own.

"For her to say go, go make something of your life, go, go do something — that was an extremely brave thing for her to do," Theron said. "Those are the sacrifices, you know, that I think you do for your children, and she always did that. She always put me first."

In the end, Theron's mother never faced prosecution. The attorney general ruled that her mother had acted to defend herself and her daughter.

Theron has said she bears the scar of that night on her heart, like a tattoo. "It's a part of me, but it doesn't rule my life," she said.

Positive Outlook

Theron considers herself "very lucky" and that she doesn't go through her life suffering.

"I have an incredible life!" she said. "I love my job. I have beautiful people around me. I'm in love with an incredible man. My career is beautiful."

That "incredible man" is actor Stuart Townsend (The League of Extraordinary Gentlemen), who has been Theron's beau for 2 1/2 years. "The lotto was scratched and I won," Theron said. "I don't think I could have imagined a love like that."

Still, it cannot be an accident that Theron has a triumph now in Monster, exploring the roles of choice and fate, and the dark road from the past to the future. Danger, ambiguity — "it's the world that I know," said Theron.

But she added, "I'm dying for a comedy." She joked, "Please, I can be funny too!"

And if Theron could go back and change the past, she says, there's only one thing she would do. "I would force my parents to get a divorce. That would be it. The rest of it has been an incredible journey."