Maria Isabella Boyd's success as a Confederate spy has made her too famous for further espionage work, and now her employment options are slim. Exiled, widowed, and on the brink of poverty...she reluctantly goes to work for the Pinkerton National Detective Agency in Chicago.Adding insult to injury, her first big assignment is commissioned by the Union Army. In short, a federally sponsored transport dirigible is being violently pursued across the Rockies...

"The air pirate Andan Cly is going straight. Well, straighter. Although he's happy to run alcohol guns wherever the money's good, he doesn't think the world needs more sap, or its increasingly ugly side-effects. But becoming legit is easier said than done, and Cly's first legal gig--a supply run for the Seattle Underground--will be paid for by sap money. New Orleans is not Cly's first pick for a shopping run. He loved the Big Easy once, back when...

"Young ex-slave Gideon Bardsley is a brilliant inventor, but the job is less glamorous than one might think, especially since the assassination attempts started. Worse yet, they're trying to destroy his greatest achievement: a calculating engine called Fiddlehead, which provides undeniable proof of something awful enough to destroy the world. Both man and machine are at risk from forces conspiring to keep the Civil War going and the money flowing....