Rami Perez was fifteen years old. He grew up in a tiny town in the deep Mexican desert, called "Desierta". He had three friends with whom he had formed a gang, and called themselves the "Eagles". The Eagles sometimes competed with another group of kids, the "Hawks" in playground games. They were playing a game called "Skully", which involved flicking bottle caps along the concrete surface of a two-meter box drawn on the ground, and 13 small boxes drawn inside the large square, and the shooter must land in the first box, without touching the sides of the box; then the second box, and so on. One may also hit an opponent's bottle cap out of the box.

In the course of the game, Rami discovers that the Hawks are cheating; they weighted their bottle caps with coins and wax. Rami, a creature of his culture, decides that this is an affront to his honor, and a man's honor can only be restored through vengeance. Indeed, the Eagles find a way to make the Hawks regret their attempt to cheat. However, the Hawks then escalate the conflict, and take revenge on the Eagles. This goes back and forth several times, each attack more clever and devastating than the previous one.

Rami is is getting the revenge he requires to restore his manhood, but has bumped up against an existential threat to his soul. Father Tommassino, the village priest, has taught him and all the children from the time they were old enough to attend services that to attempt revenge is evil - "Vengeance is mine, says the Lord"; and they had all learned that disobeying the commands of Jesus would send their souls to burn in hell for all eternity. And yet, the Old Testament God called for "an eye for an eye". God himself was counseling vengeance.

Rami seeks advice on how to deal with this conflict. He talks to Uncle Li, the bookie - a Chinese Jew who had made his way down to Mexico, and was the wisest man in the village. Uncle Li suggested that he might make a pilgrimage; that he might go up into the mountains and find peyote cactus; cut off a few of the heads and chew them up, as a way of finding his spirit animal who would help him find his way between the competing philosopies.

He then consults his aunt, Tia Ynez who, to his great surprise, agrees with Uncle Li. And so Rami's friend Angel, who cultivates a secret patch of the cacti, agrees to take him. Rami experiences many hallucinations that are due to the mescaline in the peyote heads, the "buttons" as they are known. And indeed, he did find his spirit animal - an armadillo - and in the end, his spirit animal did help guide Rami through his difficulties.

However, Rami learns that his father, Mateo, who had jumped to his death years earlier, took out a loan from one of the gangsters in Desierta. Rami learns that his father's death does not cancel the debt.

The "war" is settled when the Eagles find themselves on the run from the gangsters, and things are settled permanently.