The mighty Mississippi River of the antebellum South gives the novel both its colorful backdrop and its narrative shape, as the runaways Huck and Jim--a young rebel against civilization allied with an escaped slave--drift down its length on a flimsy raft. Their journey, at times rollickingly funny but always deadly serious in its potential consequences, takes them ever deeper into the slave-holding South, and our appreciation of their shared humanity grows as we watch them travel physically farther from yet morally closer to the freedom they both passionately seek.