Mario inadvertently becomes a wetback when he sets off across Mexico with his critically ill grandmother. In an effort to locate an aunt in Tijuana, he is victimized by an unscrupulous men who deals in cheap Mexican labor, and finds himself over the border picking cotton. A truant officer proves to be Mario's salvation, but not until the proud little boy is reassured that she will not imprison him. A warm portrait of Mario and his American friends somewhat conceals the harsher facts of Mexican labor exploitation by United States farm owners. In itself, a winning story, but somewhat misleading in the depiction of the attitude toward wetbacks in this country.