Alsino, a boy of 10 or 12, lives with his grandmother in a remote area of Nicaragua. He's engulfed in the war between rebels and government troops when a US advisor orders the army to open a staging area by the boy's hamlet. Alsino tries to be a child, climbing trees with a girl, looking through his grandfather's trunk of mementos and trying to fly; he goes to town to sell a saddle, has his first drink and is taken to a brothel. But the war surrounds him. The US advisor takes Alsino on a chopper flight, but he's unimpressed. The soldiers' cruelties awake rebel sympathies in Alsino, and after an army assault backfires, the lad is fully baptized into the conflict.