Sharon Stone was so committed to playing a real-life murder victim's mother in new movie Alpha Dog she beat her co-star until his nose bled. The actress plays a character based on the mother of murdered teen NICHOLAS MARKOWITZ, and felt she owed it to the woman and the memory of her tragic son to attack the character playing one of his attackers onscreen. Stone and young co-star Ben Foster talked about the violent scene before it was filmed and both agreed the actress couldn't pretend to hit him. She says, "I was trying to figure out how to hit him, because you have to hit a person when you're doing that kind of a scene. You can't do those stunt hits because it doesn't really work in a scene like that. "I was trying to hit him without hurting him but Ben just wouldn't let me because he knew the scene really required this kind of violence and this kind of aggression. It required me to really go for him. "He forced me to aggress (sic) him and he forced me to hit him. He just kept pushing me and pushing me and I just lost it. He made me hit him until it broke my heart. It was so awful and his nose started to bleed."