Lily and Oliver arrive at their Auntie's home expecting a boring start to their summer holiday, but her old house has hidden secrets. Somehow it is connected to the recent disappearance of a school group in a nearby wood - a wood said to be haunted by the Headless Archer. By following clues and solving riddles, the friends discover more than they ever imagined. The lost teachers and students are alive but in a dangerous place far beyond Earth...