The story of a charismatic Jesuit priest and linguist, Emilio Sandoz, who leads a twenty-first-century scientific mission to a newly discovered extraterrestrial culture, Rakhat. The Jesuits go to learn about God's children, not to preach ; Sandoz and his companions are prepared to endure isolation, hardship and death, but nothing can prepare them for the civilization they encounter, or for the tragic misunderstanding that brings the mission to a catastrophic end.