At the end of the twenty-fifth century, two young women in search of their history, uncover dangerous secrets and create some of their own. Elidir is not on any official map. A dome protects its citizens from the raging storms and deadly heat outside. High walls protect them from the desert people, known as the Non Grata. In this secret city, deep beneath a mountain, lie the remains of Western civilisation. Here, Isobel, Fallow, rebel, and ongoing disappointment to her parents, forms an unlikely friendship with Mo Llewelyn, Pure, a descendant of a long-dead warlord, and daughter of the Chief of police. Together they solve a 400-year-old murder and uncover more than they ever bargained for