All page numbers are from Douglas A. Anderson's The Annotated Hobbit.

Chapter Four: Over Hill and Under Hill

Thorin and Co. attempt to cross the Misty Mountains, with eventual success and many adventures.

The beginning of this chapter, according to the author in letter 306, is based on an experience of his in the mountains, and also mentioned in letter 232.

Things start getting sinister and gloomy again: "The nights were comfortless and chill, and they did not dare to sing or talk too loud, for the echoes were uncanny and the silence seemed to dislike being broken..." (The Annotated Hobbit.101)

During an incredible storm, described as a "thunder-battle" (The Annotated Hobbit.103) they take shelter in a cave. There, Bilbo ends up saving them, when he is the first to notice the goblins stealing their pack animals. It turns out that the cave is the back door to the goblins cave networks under the mountains. Still, the alert turns out to be little good as they are captured almost instantly and taken into the goblin tunnels.

After the Great Goblin, the leader of the goblins decides to imprison Thorin and company, Gandalf, who had stayed out of sight until then attacks with lightning. During the chaos, the Great Goblin is killed, and the dwarves and hobbit manage to escape. However, though they are free of the goblins, they are still lost underground and things soon get worse.

The goblins soon take up pursuit and Bilbo ends up separated from the dwarves.

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