Adventures of Huckleberry Finn, often described as Mark Twain's sequel to the Tom Sawyer book that preceded it, begins by recapping the adventures of two boyhood friends, Tom Sawyer and Huck Finn.

In summary of this best-selling novel, the story begins by telling the reader that Huck, now adopted by two overbearing, prissy old maids, isn't too happy with his new life of manners and cleanliness, and wants to return to his old life. Tom convinces Huck to stay where he is by telling him that if he remains, Huck will be able to join Tom's new gang of robbers. Semi-wealthy from the reward of gold they found in the previous book, Huck becomes a target for his drunken, bum father, Pap. Huck goes to hide in the woods in order to escape everyone but soon tires of his isolation. When he finds an abandoned canoe, he shoves off down the Mississippi and into a life of pure adventure, with Jim, the runaway slave of his adoptive spinsters.

Together, Huck and Jim spend their days and nights drifting down the river, each of them in search of freedom. Metaphorically, the raft comes to represent an escape for the two boys; the outside world stays in chaos as they watch, comfortable with simple things and good companionship. They don't have to answer to anyone for anything. As they try to maintain this ideal life shielded from other people and the problems they bring, unsavory things from the shore keep interrupting their utopian life. Huck describes it: "We said there warn't no home like a raft, after all. Other places do seem so cramped up and smothery, but a raft don't. You feel mighty free and easy and comfortable on a raft."

Despite Mark Twain's claim that his Huckleberry Finn carried no moral to the story, there is one. Jim had been captured, so Huck decided to tell Miss Watson where Jim was, but deceiving his friend would also mean that Huck had to return to his unhappy life in St. Petersburg, too. It was a time of moral struggle for Huck, because he was faced with doing the right thing, which would end in unhappiness for both the boys, and doing the wrong thing so they could continue on with their frivolous way of life. Here are Huck's thoughts:

It was a close place. I took . . . up [the letter I'd written to Miss Watson], and held it in my hand. I was a-trembling, because I'd got to decide, forever, betwixt two things, and I knowed it. I studied a minute, sort of holding my breath, and then says to myself: "All right then, I'll go to hell"—and tore it up. It was awful thoughts and awful words, but they was said. And I let them stay said; and never thought no more about reforming.

Mark Twain's Huckleberry Finn expressed in those words what many people struggle with when faced with making the morally right decision that may not bring the best results for them personally.

Mark Twain's characters are also very representative of the people in the South, as well as the social environment of the time. Consider Jim's dialogue, spoken in typical slave dialect, when he discovers a dead man in an old house and is trying to keep Huck from seeing the corpse because it's Huck's father: "It's a dead man. Yes, indeedy; naked, too. He's ben shot in de back. I reck'n he's ben dead two er three days. Come in, Huck, but doan' look at his face - it's too gashly." It is also this attention to detail, as well as the use of what is now considered to be racist language, that has caused controversy over Adventures of Huckleberry Finn and The Adventures of Tom Sawyer.

Through the adventures down the river of these two friends, Huck learns many lessons about life, which help him become a better person. Mark Twain's Huckleberry Finn begins to understand humanity as he develops a conscience, particularly as it relates to his harboring of Jim:

It hadn't ever come to me before, what this thing was I was doing. But now it did; and it staid with me, and scorched me more and more. I tried to make out to myself that I warn't to blame, because I didn't run Jim off from his rightful owner; but it warn's no use, conscience up and says, every time, "But you knowed he was running for his freedom, and you could a paddled ashore and told somebody.

Mark Twain's Huckleberry Finn has remained the jewel of the many works produced by him. It has also proven that Twain's exploration of the moral and racial world of that day is still relevant to some of the same ethical and racial pressures of modern times.