Rella has known the rumors of technology are true ever since she witnessed a spacecraft fall from the skies. But, on Arcadia, speaking that truth can get you hanged as a heretic. Only her collection of blades offer a glimmer of hope against Arcadia's ruthless dictators.

Though often lacking in social graces, Rella, a governor's daughter, suffers no lack of hand-eye coordination or resolve to survive after her father's wrongful death. When she gets word that the fanatics who executed her father have seized her only remaining friend, Rella knows it is time to put her training to the ultimate test. She must find a way to break into the Omi's Sanctuary, buried beneath their capital city.

Help arrives from the most unlikely of sources: a traveling Omi monk with a hidden agenda of his own. He seeks safe passage, while Rella needs his navigational knowledge of the underground maze leading to the heart of the Omi's stronghold. The pair must put their differences aside as the rescue mission morphs into a quest to expose the secrets concealed by their oppressors—and possibly even unveil the true history of humankind.