This article aims to explore a constellation of individual-attachment, family-attachment, and group-attachment experiences, as well as other psychosocial, cultural, and political factors, which contributed to the dual filicide perpetrated by Captain Gonzalo de Aguilera Munro—a count, landowner, cavalryman, and propaganda press officer for General Francisco Franco's army during the Spanish Civil War. Learning from Luis Arias González and, above all, Paul Preston's biographies of Captain Aguilera, the article will employ a combined methodology of historical investigation, psychiatric clinical formulations, and group analysis. In doing so, it will take into account a highly complex context of brutal group dynamics of national depression and exaltation, unresolved trauma, military rebellion, war, genocide, holocaust, and dictatorship.