In early 18th century Peru, an old Inca rope bridge collapses, plunging five travelers to their deaths in the Andean chasm below. Brother Juniper, who was within minutes of being on the bridge himself, becomes obsessed with discovering how five people of differing class and circumstances came to be on the bridge at that moment. The Catholic friar wants to know if it was mere existential happenstance or part of God's cosmic plan.
After researching the lives of the victims for five years and publishing his findings in a book, he is accused of heresy by the worldly Archbishop of Lima and is put on trial for his life by the Inquisition.