(previously published as Sky Castles)
Caishel saves Sire Ailan's life and accepts a job as his page in the floating castle of Ardon. Anything is better than living on the streets as a male urchin.
Ailan immediately discovers his page is a woman, but keeps this knowledge to himself, despite his growing attraction to her.
Caishel longs to tell Ailan the truth but confession could put her in danger. Circumstances eventually force her to reveal her true identity and, like a caterpillar evolving into a butterfly, Caishel marries Ailan. After his grandfather dies Ailan inherits the title and lands of the Duke of Lan.
Caishel is convinces the ghost like Eos have something to do with the accidents that keep happening to Ailan and she decides to investigate by donning her street urchin disguise.
Capet Sard helps farm girl Lise obtain a job as nursemaid in the floating Castle of Lan, and love blossoms between the noble and the servant. Sard is called home to Rak and shortly after his departure Lise discovers she is pregnant. She stows away on a ship to Rak but after landing, gets lost in the desert. Rescued by the spiritual Eos, Lise finishes the journey on foot but Brenauf, the new Duke of Rak and an old adversary of Sard’s, captures her. The duke’s inability to run Rak causes many of his nobles to question whether he is the true heir.
Miserable, pregnant and frightened for her baby's welfare, Lise can see no way out of her captivity. Sard and the Eos attempt to save Lise. Failure could mean disaster for Rak and the whole planet of Hejmen.
Tazia is petrified of her first night with Duke Robard, her new husband by an arranged marriage, because her father’s mistress has told her alarming tales of what he will do. Robard is patient with her but their union remains unconsummated. They learn to work together, but intimacy evades them.
A strange illness begins to decimate the ghostlike Eos, decimating their already small numbers. Tazia and Robard work together and put their personal problems aside while they help the Eos avoid extinction.
The Eos discover their recent visitors were not from the other known tribes and research points to a lost tribe in the Pator area. Tazia and Robard set out on a journey of discovery to find the lost ones. Without the Eos the planet will die and this will mean the end of humanity on Hejmen.
Zaeyen's marriage to a neighbouring duke’s son is intended to save her father's estate, but the groom is cruel and threatens his betrothed. Zaeyen believes if she finds the Eos, who disappeared many centuries ago, t will save the planet and there will be no need for her to marry. She goes in search of the ghost like Eos and on her way meets Kade, a hero of the common folk. Kade joins her in the search and they battle through thirst, hunger and capture to reach their goal. The planet of Hejmen is dying and only the Eos can revive it, but do the spirits still exist and if they do, will they be willing to help the humans?