Them — Fay Sampson

Berlewen is trapped in a past she has not chosen, denied any modern technology. Honesty, her servant, longs to free her family, now enslaved in a weapons factory. Only Map, the boot-boy, seems sure of the freedom promised to them in an ancient song. They are all prisoners of Them. One day, a summons from Them forces Berlewen and Honesty to flee and brave the mysterious being that guards Glastonbury. Their quest is to find the legendary Prince and free their people from the ruthless domination of Them. But does the Prince really exist? How will they recognize him? And even if they find him, how can anyone defeat Them?