Kit Livingstone is stuck in prehistoric times, but has discovered a link from the Bone House to the fabled Spirit Well, a place of profound power. On a cave painting he discovers the same symbols he remembers from the Skin Map. Mina his erstwhile girlfriend is holed up in a mountaintop monastery learning all she can about ley travel from a monk named Brother Lazarus. Meanwhile their evil nemesis, Lord Burleigh, thwarted in his hunt for Kit, discovers a descendant of the Skin Map's creator flogging rare ancient artefacts to get himself out of debt. Cass Clarke enters the quest, transported inadvertently from an archeological dig in Arizona. In 1950's Damascus she encounters the last remaining members of the Zetetic Society, who need her to track down Kit and his ancestor Cosimo, to help them unlock the biggest mystery of all: the purpose of the universe. Through all this the influence of Cosimo lives on, and at the heart of the mystery lies The Spirit Well. This is the third book in the five volume Bright Empires series, a multidimensional, time-bending fantasy from a master storyteller.