The Cerulean are an all female utopian society who have moved from planet to planet in their magical space city for millenia. They have been attached to the current planet since The Great Sadness—an ambiguous time in Cerulean history when ceruleans died and some cultural traditions were changed, such as visiting the people of the planets to which they connect via a magical tether that is both broken and established by the sacrifice of a chosen member of their society. Sera is chosen to break the tether just before her eighteenth birthday. She accepts her fate and willingly sacrifices herself to set her people and her beloved city free. But it doesn't work. She doesn't die and the tether isn't severed by the magic in her blood. Instead she is captured by twins whose father is a wealthy showman with sinister intentions. While Sera searches for a way to escape and return home, her best friend, Leela, and one of Sera's three mothers begin to discover that all is not as perfect in the Cerulean city as it may seem. The story ends as Sera makes her escape from the freak show and Leela makes a gruesome discovery hidden under the Cerulean temple.