When a gwyllion wind engulfs 13-year-old Apple Standish outside of her Irish middle school, the veil between her everyday reality and an unseen world is momentarily torn away. Apple catches a glimpse into another ether-world, where she locks eyes with Tak, the feline leader of a clandestine order of numinous nine-lived cats, known by tree folk and fey alike as Magnificats.
The effect of this unseasonable sheegee sweeps Apple out of her attachment to bitterness over her parents' divorce and into a massive struggle to save the world from a powerful demon wind she accidentally releases.
Along the way, she meets her first true friend, an awkward and isolated foster child with a gift for healing animals named Krystal, as well as Magnificat leaders, including the Clouders, constant allies of the human race throughout their time on earth, both openly and secretly. The events set in motion entangle both girls in a magical struggle against a terrifying enemy, and ultimately bring them to a new understanding of courage, purpose, loyalty, and family.