 Stuart Angel was an undergraduate student at Federal University of Rio de Janeiro's School of Economics when he joined the left-wing urban guerrilla group Revolutionary Movement 8th October ("Movimento Revolucionário 8 de Outubro" – MR-8).He was known by his fellow guerrillas by the codenames "Paulo" and "Henrique".He married fellow militant Sônia Maria Morais Angel Jones, who would later die in the custody of the military dictatorship's political police.