Tom finds himself at the end of his rope. He decides, once and for all, to be a criminal.
As he is walking away from the school house, from the town, from society, he begins to cry.
As luck should have it, he runs into his buddy Joe Harper, who seems to be in a similar state of mind. Joe, it seems, has just been whipped by his mother for drinking some cream, and has decided to leave his old life behind.
The boys decide to be companions for life, and discuss possible plans. Joe wants to become a hermit, but Tom quickly convinces him that piracy is the way to go.
They decide to go live on Jackson's Island, a little piece of land in the middle of the Mississippi.
They find Huck and get him to join their crew, then set about letting everyone know that soon the town will "hear something" (13.6).
That night, Tom, Joe, and Huck meet up, each bringing with them some stolen booty: a boiled ham, some bacon, and various other supplies.
They steal a small raft and make the short trip over to the island.
Once there, they set up camp, and get down to discussing the particulars of piracy – which Tom claims to know all about. Pirates, he tells his companions, take ships, steal money and bury it, kill people, etc. But they're nice enough; he and Joe agree to just kidnap women and not kill them.
When they lie down to sleep, Tom and Joe are filled with guilt, for running away, and for stealing. They say their prayers – in order that they might not be struck down by divine lightning – and resolve never to steal as long as they're pirates.