Halfhand, Jon and company move north through the mountains. Halfhand knows Jon didn't kill the wildling girl, but he doesn't care because he only wanted to test Jon to learn what sort of person he is. If he'd really wanted her dead he'd have asked someone else to do it.
Jon goes to sleep and dreams he is Ghost. He climbs to the top of a ridge and sees Mance Rayder's camp and its exact location. He wakes up and tells everyone and they all believe him and use this intelligence to decide it's time to go home. There is further proof in that Ghost really has been injured by an eagle, just as in the dream.
Now, this all seems a bit unfair to me. To get his super powers, poor Bran had to fall off a building, get crippled, endure months of apparently meaningless nightmares, more months of confusion, and have the deaths of his friends predicted, his predictions disbelieved and finally confirmed before it became clear that the dreams were meaningful. Jon has one good nap, gets all the good information, and is able to make use of it in about three pages. And he still has the use of both his legs. Where's the justice?
Also in this chapter we are introduced to a new character who gets left behind on a mountain to martyr himself attempting to delay the company's hundreds of pursuers with a single bow.
