What was it that flew over with such a terrifying roar? Was it, as many said, the devil, or was it that thing a few had heard of, a flying machine? And those electric lights at Jacob Gallo's farm, were they witchcraft or were they science?

The theme of this harshly powerful novel is the impact of modern technology and ideas on a few isolated, tradition-bound hamlets in the aftermath of the Mexican Revolution of 1910. The old ways are represented by Epifanio Trujillo, the cacique of the region, now ailing and losing his grip on things; by ancient Madre Matiana, the region's midwife, healer, counselor, and oracle; by penniless Rómulo and his wife Merced. "Progress" is represented by Don Epifanio's bastard son Jacob, who acquired money and influence elsewhere during the Revolution and who now, against his father's will, brings electricity, irrigation, fertilizers, and other modernities to the lean lands—together with armed henchmen. The conflict between the old and the new builds slowly and inexorably to a violent climax that will long remain in the reader's memory.

The author has given psychological and historical depth to his story by alternating the passages of narrative and dialogue with others in which several of the major characters brood on the past, the present, and the future. For instance, Matiana, now in her eighties, touchingly remembers how she was married and widowed before she had reached her seventeenth birthday. This dual technique is superbly handled, so that people and events have both a vivid actuality and an inner richness of meaning. The impact of the narrative is intensified by the twenty-one striking illustrations by Alberto Beltrán.