Freefall (Tunnels, #3)

After Deeper, can the Tunnels adventure be any more dangerous? And where will it end? Will Burrows and his gang are far from finished as they free-fall down a subterranean pore. As they experience reduced gravity, the dark mysteries of the deep unfold and they discover a strange fungal shelf, which not only reveals artifacts from ancient civilisations, but clues to a lost land at the end of the Earth. This title is the third in the thrilling "Tunnels" series - an international publishing sensation.