Daisy Thistledown has recently escaped from boarding school, and has a mystery to solve. The trail will lead her through a hidden doorway to the Greenwild, a rich and verdant land bursting with magic. There, Daisy finds herself confronting a dangerous presence that threatens green magic on both sides of the door.
Daisy must band together with a botanical prodigy, a boy who can talk to animals, and a cat with an attitude, to channel the power that can save the Greenwild - and her own world too.