Juan, a young man convicted of terrorism, is given amnesty from a Lima prison; he boards a bus to return home and, in his mind's eye, recalls events in his village near Huaraz when he was 10 or 12. His father is long dead, his mother lives with Fermin, secretly a sympathizer with the Communist guerrillas in the hills. Town leaders are assassinated at night. When Juan discovers Fermin's secret, Juan is spirited away to the guerrillas to learn Marxist slogans and how to fight. When the band decides to attack the town to avenge the death of a comrade, Juan must choose.