Bücher der Reihe Mycelium Seep

When Khalek, a teenager from an underground city discovers a disease inflicting the roots penetrating from above ground, his mind merges with that of Laura - a vehicle designer. Khalek's people are barred from the surface, which is controlled by xenophobic humanoids. In order to stop the disease, Khalek and Laura embark on a journey in an attempt to communicate with the humanoids.