Bipa does not believe in fairy tales. She's not interested in anything beyond the caves where her people live. Her friend Aer, on the other hand, seems to get farther and farther from reality every day. One day, Aer sets off on a dangerous journey in search of the legendary Ethereal Kingdom, a place where suffering doesn't exist, and people never feel cold or hunger. Bipa follows him, trying to stop his absurd quest, but soon she finds herself pursuing her own dreams too. The latest novel by one of the most important authors in contemporary Spanish-language literature for young adults.