Jill Tyler and her minister husband Rob Tyler adopt two children, Catherine and Eric. Eric is a sweet and timid child, while Catherine seems to come across as being the same. Catherine soon displays outbursts of violent rage for no apparent reason, affecting her behavior and interaction with others. At first, some of her violent acts (such as killing a clutch of baby birds and attacking Eric while he sleeps) go unnoticed, but when it progresses to tearing her room apart and stabbing the family dog with a needle, Jill and Rob sense something is wrong. They attempt to ask Doris, the children's caseworker, about anything in Catherine's past that might explain it, but Doris cites confidentiality laws and only suggests that Jill and Rob bring the children back if they're unable to handle them.
Following an equally disturbing incident where Catherine engages in sexually inappropriate behavior with her adoptive grandfather, Jill and Rob take her to a psychologist, but she puts on a good show while there and convinces him that there's nothing wrong. A short time later, Jill notices fresh bruises on Eric, and though he's initially scared to say anything, she gets him to admit that it was Catherine who inflicted them, though these are relatively minute compared to her next episode, where she repeatedly smashes Eric's head on the concrete basement floor, landing him in the emergency room.
At this point, Doris finally admits the truth about the children's past: after receiving a concerned phone call, she rescued the children from an abusive and neglectful home, which was one of the worst she'd seen. Although Eric was in bad shape, it was nothing compared to the condition Catherine was found in, and no adults were present at the time (their biological mother was hospitalized with pneumonia, while their biological father was presumably off on a drunken bender).
Doris then reveals that the children have an older biological sister named Stephanie, whom she and Jill track down at a topless bar. After sitting down with them, Stephanie, a bitter young woman, has a harrowing story of her own to tell: she was sexually abused by her father as a child, and after she began fighting back, he turned his attention over to Catherine (who was just a baby at the time), thus explaining the root of her violent misbehavior.
After yet another violent incident in which Catherine cuts a classmate with a shard of glass, Jill and Rob pay another visit to Doris, who reveals that she had previously moved the children from foster home to foster home, hoping that something would work for them. She then gives the couple a book called Kids Who Kill, and after reading it, Jill describes it as "chilling" and feeling like it was a perfect description of Catherine. It is at this point that Doris suggests a controversial treatment method for Catherine: holding therapy, which is practiced by the book's author, Dr. Rosemary Myers. Rob feels as though Catherine is a lost cause and suggests they just keep Eric, but Jill reminds him that "God gave us these children for a reason" and that they have to do whatever they can to help Catherine.
After traveling to the clinic, Dr. Myers examines Catherine, and though she initially tries to put on the same act that she did for the last therapist, Dr. Myers uses reverse psychology to get Catherine to admit her past acts of violence. Afterward, she tells Jill and Rob that they have "a very sick little girl", and the lack of an opportunity for bonding after Catherine was born left her with an inability to attach. She offers to try to help Catherine, but acknowledges it can go either way.
During their first holding therapy session (which involves Jill, Rob, and Dr. Myers holding Catherine down while Dr. Myers deliberately provokes her rage), things start out well, but Jill senses it's going too far. Dr. Myers reminds Jill that she needs to trust her, and the session resumes, ending successfully after an enraged Catherine admits a desire to re-enact her past acts of violence with the three of them, giving them a glimpse of the pain underneath her rage. While the procedure normally takes place over a 6-week period, Dr. Myers realizes that Jill and Rob need to get home to Eric (who is in the care of Rob's parents while they're away) and believes the couple can successfully conduct the sessions at home, so she gives them permission to do so.
Shortly before their return home, another disturbed child named Justin starts a fire at the hotel, and when Catherine is inadvertently left alone in the room during the evacuation, it sets off an apparent feeling of panic in her, culminating in an incident where she tries to stab Rob with a knife concealed inside her teddy bear as he sleeps, but is caught in the nick of time.
Returning home, the couple discusses the prospect of being separated from one another to give Catherine individual bonding time with each parent, and though initially uncertain, they agree it's best in order to allow her a chance to heal. As the two have another holding therapy session with Catherine, a breakthrough occurs: when Catherine starts to cry afterward, Jill does the same, and Catherine attempts to comfort her. The film ends with Catherine telling Jill and Rob that she loves them as the three tearfully embrace.
Prior to the film's release, a 1990 documentary entitled Child of Rage: A Story of Abuse was produced by Gaby Monet based on interviews conducted with the film's real-life inspiration, Beth Thomas. It aired on HBO as part of their America Undercover series. The film consists of interviews with Beth Thomas by a therapist (Ken Magid), followed by footage of her treatment and partial recovery at a treatment center for children. The documentary was released shortly after Magid's book High Risk: Children Without A Conscience, which portrays children with reactive attachment disorder (as Thomas is labelled in the film) as "murderous psychopaths," contrary to its actual definition in the Diagnostic and Statistical Manual of Mental Disorders fourth edition but in accordance with the fictional diagnosis of "attachment disorder."
Nevertheless, a distinction has to be made here between 'attachment theory' and 'attachment therapy'. Attachment theory has over 70 years or evidence-based research, and its principals have been proven is numerous scientific studies (e.g. Harry Harlow's experiments). Attachment therapy is in no way connected to attachment theory, yet it may have been the intention of attachment therapy practitioners to align their extreme and unproven practices with the respect of attachment theory. There was a vacuum created after the discoveries of attachment theory, for it only proved how mental and emotional conditions, such as Beth's, are caused, and attachment theory does not detail, describe or indicate any practices that lead to the recovery of the mental and emotional conditions it proved arise from neglect or abuse of the attachment process. It was this vacuum of 'no treatment for proved mental and emotional conditions' in which attachment therapy proponents grew.
Beth Thomas's adopted mother Nancy Thomas has been a leading proponent of "attachment therapy" (originally known as "Rage reduction therapy", thus the title) since the documentary was made, a highly controversial form of psychotherapy regarded by the American Medical Association as pseudoscientific and abusive. Beth Thomas, a former patient of the "Attachment therapist" Connell Watkins, would later - as a freshman - testify on Watkin's behalf in the Candace Newmaker trial, where Watkins was convicted of child abuse for administering "rebirthing" therapy which caused the asphyxiation of her "patient". Thomas has since graduated from the University of Colorado with a bachelor's degree in Nursing and became an award-winning Flagstaff Medical Center Registered Nurse.