This is a thrilling adventure story about a mysterious underground world.
Fourteen-year-old Will Burrows lives with his parents and younger sister Rebecca in London. He has little in common with any of them, except for a passion for digging, which he shares with his father, a museum curator and doctor of archaeology. When his father suddenly disappears after a row with his mother, the police believe he has just gone away for a while to cool down. But Will is unconvinced, and decides to investigate with his best friend Chester. After dark, the two boys break into the museum where Dr Burrows worked and find his journal. In it, he talks about a strange group of pallid people; a bizarre glowing sphere; and a man named Martina who is reputed to have built a network of underground tunnels, although there is now no evidence that they ever existed. Sure that his father has gone to find the tunnels, Will and Chester follow in his footsteps. Soon they find themselves deep underground, where they unearth a dark and terrifying secret - a secret which may cost them their lives...