Each year, in the Mexican town of Contepec, migrating Monarch butterflies spend the winter in the temperate forests of Mexico. This children's book (ages 8-12) is an adventure story about two courageous cousins Eréndira and Corina. With the help of their community as well as Maria the Monarch butterfly, who speaks to them in their dreams, they save the lives of millions of Monarch butterflies threatened by illegal logging and traffickers of wild animals. Together they help preserve the natural and cultural wealth of their homeland.

In an afterword "The Monarch: A Tireless Traveler" Betty Ferber describes the life and evolution of the Monarch butterfly, its migration from North to South America, and the establishment of the sanctuaries in Mexico and the laws that protect them.