In an alternate New Orleans caught in the tangle from the American Civil War, the wall-scaling girl named Creeper yearns to flee the streets for the air–in particular, by earning a spot on-board the airship Midnight Robber. Creeper programs to gain Captain Ann-Marie’s trust with details she discovers in regards to a Haitian scientist and a strange weapon he calls The Black God’s Drums. But Creeper also has a magic formula herself: Oya, the African orisha from the blowing wind and storms, talks inside her head, and may have got her very own ulterior motivations. Shortly, Creeper, Oya, as well as the crew from the Midnight Robber are drawn into a perilous objective aimed to avoid the Black God’s Drums from becoming unleashed and wiping out the entirety of New Orleans.