Jupiter is a horse-breaker and coach driver, and was born into slavery. During a freak electrical storm, he is struck by lighting which gives him the power of immortality, and makes his scars translucent. Jupiter escapes to the North and finds the abolitionist and former enslaved person, Harriet Tubman. Together, they plot to smuggle run-away slaves through the underground railroad. Jupiter continually puts his life on the line to help others knowing he cannot be killed,