During the continuing cold spell, James keeps stealing wood to help several families survive. One Sunday, Sadie tells James that she overheard Miss Watson telling Judge Thatcher that she plans to sell James to a man in New Orleans. James immediately understands that sale would separate him from Sadie and Lizzie and push him farther from any hope of freedom, so he decides he must disappear before he can be taken.

James hurriedly gathers food, comforts Lizzie, promises Sadie he will return, and secretly leaves for Jackson Island. He hides by the river until dusk because crossing in daylight would expose him. As he waits, James feels both fear and anger, but he also reflects that an enslaved man has no safe way to direct anger at the people truly causing his suffering.

After dark, James pushes a log into the Mississippi and lets the current carry him toward the island. A snag catches his leg in a trotline, nearly making him miss the island or drown, but he frees the line and gains three catfish from it. Exhausted, soaked, and freezing, James reaches the island, guts the fish, avoids lighting a fire that night, and buries himself in leaves to survive until morning.

The next morning, James hears someone in the woods and discovers Huck Finn on the island. Huck explains that he killed a pig, spread its blood around Pap's cabin, and made everyone believe he has been murdered so he can escape Pap. James quickly realizes the danger: he has just run away, and Huck's supposed murder could easily be blamed on him. James explains that Miss Watson intends to sell him, and Huck begins to grasp that slavery allows even a liked enslaved man to be torn from his family. The two boys make a fire, eat fish, and watch a ferryboat searching for Huck's body with cannon fire and a loaf of bread meant to find a corpse. Seeing Judge Thatcher, Bessie, Aunt Polly, and the search party confirms that Huck is believed dead and that both Huck and James are now in even greater danger if they are found.