Quintessence Sky continues where the events of Quintessence (Tor Books, 2013) left off.

At the edge of the flat Earth, a strange fire in the sky burns, altering the balance of the elements and threatening all life on Horizon Island. Matthew Marcheford experiments to determine the cause, while the growing animosity of the manticores and the arrival of more ships from Europe jeopardize the colony's fragile peace. When Matthew's fiancee, Catherine Parris, is betrayed and abandoned deep underground, the secrets she uncovers there may be Horizon's last hope.

King Philip of Spain,...