The skeleton lay on its back. The jaws gaped and one arm lay across the chest as through flung there to ward off a blow . . . The Tangle is a long, narrow stretch of derelict land, a wilderness of weeds and rubbish with an old railway tunnel yawning blackly at one end. No-one - not even bullying Gary Deacon - dares venture far into its sooty darkness. But it is here that twelve-year-old Tan and his friends make a grisly discovery - a discovery that is to plunge them into a terrifying adventure as the tunnel slowly unfolds its sinister secret . . .