The year is 1770, and new mystical movements are sweeping across the Jewish communities of Poland and Ukraine. A traveling Jewish preacher arrives in a small town on the eve of Shabbat, eager to impart his new vision and strange practices, but the town's Jews send him away in scorn and contempt. However, after the preacher returns to save the town's children from a horrific pestilence, which had proven impervious to all medical interventions and fervent prayers, he is embraced and beloved. But then he reveals the mad brutality and nihilism beneath his doctrines of joy and wonder at the splendor of divine creation; he leaves a trail of bitterness and suffering in his wake.