Luna, a teenage student from Madrid, manages to convince her parents to let her spend the summer with her aunt Emma, an enigmatic woman who she has not seen since childhood. Once there, Luna discovers that her aunt is a sorceress with real powers, a descendant of a long line of witches that goes back for centuries. While Luna begins to learn the secrets of magic, without much success, her aunt confesses that for weeks she has felt somebody trying to get into her mind to read her thoughts. Despite having used her most powerful spells against this being, she has not managed to get rid of it. One night during a dream, a woman asks Emma for help to save a world called Eilean, where all magic is running out. To help them, all Emma has to do is carry out a ritual to change plain, with no danger involved whatsoever. However, during the ritual, something goes horribly wrong and Emma falls dead, struck down by a bolt, in front of her niece. Luna decides to take her aunt's Book of Shadows, the book she used to write down all of her spells, with her. Before closing the book, she writes down a promise on the last page that she will find the being who killed her aunt and avenge her death. Weeks later, back in Madrid, Luna discovers four new words under her promise, written in Emma's handwriting, that would turn her world upside down: "I'm not dead." A story of magic and witchcraft, parallel worlds, adventures and romance... Follow Luna into a world of dragons and hippogryphs, elves and dryads, powerful wizards and dangerous sorcerers. Do you dare to accompany her on her trip to Eilean?