Ganymede is the fourth novel in Cherie Priest's steampunk Clockwork Century, moving the series south to a New Orleans occupied by the Republic of Texas amid a Civil War that has dragged on for twenty years. It centers on Josephine Early, a shrewd madam and Union agent, and Andan Cly, the air pirate captain first met in Boneshaker and Clementine, now trying to trade smuggling for a lawful life.
The plot turns on the Ganymede, a lethal prototype submarine that could tip the war if it can be delivered to Union forces in the Gulf. Priest weaves period-accurate New Orleans texture, zombies rising from the Blight-touched fringes, and a cast of pilots, spies, and dockworkers into a heist-shaped adventure that is as much about second chances between two former lovers as about the machine itself.
Faster and more romantic than earlier entries, Ganymede broadens the series geography and advances its overarching war plot.