"Do you ever stick pins in people?"

"Yes."

"Who?"

"My brother."

"And what are you trying to do to your brother?"

"Kill him."

The man asking the questions is a clinical psychologist. The person answering them is a 6-year-old girl named Beth, who also matter-of-factly contemplates torturing her pets and murdering her parents. Her story is told in an undeniably powerful 27-minute documentary, "Child of Rage: A Story of Abuse," to be shown as part of the "America Undercover" series at 10 tonight on Home Box Office.

Beth was physically and sexually assaulted during the first year of her life by her real father, according to the psychologist, Ken Magid of Golden, Colo., who videotaped some of his sessions with the child. As a result of severe neglect and abuse, Beth and children like her may fail to develop a human conscience or the ability to bond with other people. They lack, in other words, the most elemental aspects of socialization.

As the documentary shows, Beth got and is getting treatment, and may eventually function normally. But a viewer is left to wonder about children raised in similar straits who are never helped, and what those children grow up to be.

Beth and her brother were adopted in 1984 by a Southern minister and his wife, who apparently knew nothing of the earlier mistreatment. It wasn't long before they realized something was terribly wrong. They were forced to lock Beth in her room at night to prevent her from attacking, or even sexually molesting, her little brother. We see the brother only in still photographs.

The parents later realized that the emotional scars ran so deep that Beth required intensive psychiatric care and isolation from those she might casually, unthinkingly harm. A teacher at the special school where Beth was sent says she has seen worse cases: "People don't think a 9-year-old is capable of cold-blooded murder, but they are."

The documentary, produced by Gaby Monet in cooperation with the National Committee for the Prevention of Child Abuse, is well done as far as it goes, but that isn't far enough. Much more information about Beth's background and about the frequency of such cases would be helpful. Perhaps it was thought that dry data would frighten viewers off. "Child of Rage" is appallingly light on context.

In terms of programming, it seems odd encountering a chilling dose of reality like this sandwiched between HBO's usual frivolous movies. In addition, it suggests poor judgment on HBO's part to have scheduled some of the future showings of this documentary during daytime hours when children control TV sets. Beth's descriptions of sexual abuse are specific and clinical and not the sort of thing other children should see, at least not without guidance from an adult.

Despite the misjudgments, "Child of Rage" has value as a study of the effects of child abuse at its most heartless and virulent. The hopefulness in the story is that such children can be helped. Near the end of the program, as she talks again about her ordeal, Beth's eyes fill with tears. It's the first sign of emotion she has shown to the camera. So in some ways, they are not tears of pain, but of joy.