Kristy Petersen's transition from compassionate nurse to mercy killer is insidious. She suffers burn-out as a critical care nurse. What finally pushes her over the top isn't one individual thing, but a compilation of family, romantic and work stressors. Add to the mix her growing concern for the habits of modern medicine in keeping alive elderly people and others with terminal illnesses. When a patient dies accidentally through omitting medication needed to keep her alive, Kristy is surprised at how powerful she feels. She convinces herself she's being merciful by allowing her patients to die. The next step to active mercy killing is inevitable. Being caught, convicted, and sentenced to prison does nothing to rehabilitate her. After serving a small portion of her sentence, she is paroled. But just before leaving, she commits an act that will result in the death of an inmate. However, she takes great pains to assure that she won't get caught this time. So much for rehabilitation.