The case of a 48-year-old woman accused of killing at least 12 elderly women and attempting to kill another one during the last 3 years is presented. Extensive neuropsychological, electrophysiological, and neuropsychiatric testing showed no evidence of a DSM-IV-TR Axis I diagnosis, but a decrease in executive functions and abnormalities in the processing of affective stimuli were found. Behavioral and psychophysiological studies revealed dissociation between knowing how to behave and actually behaving in socially acceptable ways. According to the woman, killing was just her response to "humiliating situations." Two potentially significant conditions in her past history are found: (i) childhood abuse; and (ii) multiple head injuries. It is conjectured that the nature of her crimes, paranoid and personality traits, a probable frontal brain dysfunction, as well as a specific demographic and social context represent unusual factors accounting for her violent behavior.