Hollydeva, a 12-year-old girl, meets Astrello, the Star Boy, in Georgeburg Castle, where she lives and interrogates prisoners with her father, the Grand Inquisitor of the Nine Nacharya. She is commissioned by Guuz, the Daisy Deva, to fight the machinations of the alchymists, whose changes are leading to the death of the bees and thus of the plants and the Yrth. But the alchymists are supported by the wizardeurs and sorcerers, who have been boosted by the ascension of a boy with a scar on his forehead, when they attack Georgeburg Castle. Ultimately, however, Saphed Zronn, the most powerful of the Nine Nacharya, is Hollydeva’s adversary.

When George’s Castle burns down, she receives a medallion from the Bhogi, her old mentor among the Nine, as he wants her to become his successor and thus the first woman among the Nine Guardians of the Yrth.

Hollydeva flees with Astrello and her wounded father to her grandmother’s estate, where strange otherworldly beings appear. The grandmother takes them to Linden Island, a monastery school for young mystics, where she herself was once a master and where Hollydeva’s mother, who is dismissive of her, is now the garden master.

Hollydeva becomes “Sister Scorpio” and is able to make friends with the other eleven novices in her year, who are also named after zodiac signs. She learns about the different branches of mysticism and is herself accepted into the Yana of the Ravens, where Prioress Corvanya becomes her teacher and mentor.

But Linden Island is threatened by the Nereides, sea fairies, and their sea demons. Hollydeva discovers that the Nereides feel threatened by the undertakings of the abbess of Linden Island, High Maestra Tilia, and must attack. At the last minute, Hollydeva and her friends are able to save Linden Island from destruction.

The sinister Dark Master Finster, who seems to know more about her than she does, takes her with him into his world.