The majority of the 36 male offenders in the sample grew up in the 1940's and 1950's, were white, and were usually eldest sons. Most had positive personal characteristics and social factors: a pleasant general appearance, average to above-average intelligence, mothers who were homemakers, and fathers who earned comfortable incomes. Family histories, however, revealed multiple problems. The murderers felt uninvolved with their fathers, ambivalent toward their mothers, and had little attachment to younger siblings. The parents were preoccupied with their own problems of substance abuse, criminality, or aberrant sexual behavior and were often arguing. Offenders' individual development was characterized by the dominance of a fantasy life -- primarily violent and sadistic in nature -- and a history of personal abuse. Despite the intelligence and potential of these men, their performance in academics, employment, sexual relationships, and military service was poor. Interviews revealed many expressions of low self-esteem prior to the murders. These data suggest the murderers developed certain attitudes: they devalued people, viewed the world as unjust, saw life and authority as inconsistent and unpredictable, were obsessed with dominance through aggression, and preferred solo sex. To fulfill a need for a sense of adequacy and mastery of life, the murderers developed private worlds where fantasy and delusions predominated. Clues for understanding the type of criminal personality responsible for rape, mutilation, torture, and murder are outlined. A chart and two references are supplied.