In Whitehead's ingenious conception, the Underground Railroad is no mere metaphor - engineers and conductors operate a secret network of tracks and tunnels beneath the Southern soil. Cora and Caesar's first stop is South Carolina, in a city that initially seems like a haven - but the city's placid surface masks an insidious scheme designed for its black denizens. Even worse: Ridgeway, the relentless slave catcher, is close on their heels. Forced to flee again, Cora embarks on a harrowing flight, state by state, seeking true freedom.