Alvas Zuhause ist in Gefahr. Denn ausgerechnet ihre geliebten Pflanzen sollen etwas mit der Krankheit zu tun haben, die sich überall ausbreitet. Alva will unbedingt die Wahrheit herausfinden! Heimlich schleicht sie sich auf ein Handelsboot, wo sie auf ihre Reisegefährten trifft: Idris und Ariana. Zusammen bezwingen sie wilde Wasser und unbekannte Wälder. Wird es ihnen gelingen, das Geheimnis zu lüften und das Heilmittel zu beschaffen? 

Yarrow Townsend spent most of her childhood in the woods, pretending to be characters from books. She especially liked the ones where children had to survive on their own. In 2009, she went to Oxford to study English and French Literature, and discovered that the Botanic Garden was the perfect place to revise for exams. After university, she became an English teacher where she especially enjoyed taking children outside to write stories. Since then, Yarrow has found herself in jobs that usually involve getting muddy, like working with rescue horses, and learning how to use chainsaws and tractors at the RSPB. She now lives on a narrowboat and travels around the canals of England looking for more opportunities to get muddy (and somewhere to keep her own sheep).