Outside her home in Michoacan, Mexico, grows eight-year-old Isabel’s greatest treasure: an oyamel tree. Every autumn, a miracle happens-for Isabel’s tree is the wintering place for thousands upon thousands of monarch butterflies that migrate from the north. When they flutter down to roost, they transform Isabel’s tree into La casa de las mariposas-The House of Butterflies. But this wonder is in danger of disappearing forever. Isabel’s family is poor, and it has been a cruel, dry year for Papa’s meager crop of corn and beans. Soon, chopping down the tree to sell its wood may be the family’s only hope for survival. What will happen to the butterflies then?