"In the tower of Count Stelli in the ancient city-state of Agora, two children meet, apparently by chance. Mark has escaped the plague ravaging the city's slums. Lily is the servant who cares for him. At first, their only goal is survival: In Agora, everything can be bought and sold, debt is death, and Mark and Lily must barter their labor for their lives. Then comes an opportunity for them to exchange destinies: for Lily to escape the tower for the city outside, and for Mark to find refuge inside by taking a serving position with the Count. The exchange will set them on divergent paths: Mark's toward fame and fortune as an astrologer, Lily's as the founder of an almshouse for the city's poor and destitute. Yet their lives remain strangely intertwined, and it is Lily who will discover the role that each of them is destined to play in fulfilling the prophecy and challenge of the secret Midnight Charter devised by Agora's founders..."--dust cover flap.