Despite being an infrequent crime, parental homicide has been associated with schizophrenia spectrum disorders in adult perpetrators and a history of child abuse and family violence in adolescent perpetrators. Among severe psychiatric disorders there is initial evidence that delusional misidentification might also play a role in parricide. Parricides are often committed with undue violence and may result in overkill. The authors present the case of an adult male affected by schizoaffective disorder and Capgras syndrome who committed patricide. Forensic pathologists classify such cases as overkill by multiple fatal means comprising stabbing, blunt trauma and choking. Accurate crime scene investigations coupled with psychiatric examinations of perpetrator allow reconstruction of the murder stages. This overkill case is discussed in the context of a broad review of the literature.