The gyptians, Lyra, Lee Scoresby and Iorek Byrnison travel from Trollesund to the North with Kaisa following them. Lyra uses the alethiometer and tells to Farder Coram that there is a ghost in a nearby town and she needs to go there alone. Meanwhile, the teenager Will Parry and his mother Elaine are followed by Carlo Boreal and one of his man. He approaches to Elaine, asking for her husband John Parry that has been missing for a long time. Lyra convinces John to go to the town with Iorek Byrnison, and then return to meet the group. When they arrive at the town, Lyra enters in a house and finds the weak Billy Costa without his daemon. They bring him back to deliver him to Ma Costa, but he does not resist and dies. During the night, something happens in the gyptians camp.
"The Lost Boy" is another great episode of "His Dark Materials", this time introducing the character from the other world, Will Parry, that Kaisa says that will have important part in the story. The conclusion is again a cliffhanger, with Lyra kidnapped by the attackers of the camp. My vote is eight.
Title (Brazil): "The Lost Boy"