'The Hobbit' Movie: Differences from the Book - What Did Peter Jackson Change in the Film Version of Tolkien's Story?

"The Hobbit: An Unexpected Journey" runs nearly three hours, yet it covers only the first third of a book that's less than 300 pages long.

(The first film in the trilogy actually covers 114 pages of my 1973 Revised Edition paperback, to be exact.)

So it makes sense that director Peter Jackson would throw in a bit more action and information for Middle Earth junkies, but what did he change?

To give the relatively self-contained story a place in the grander mythology of Tolkien's works, the filmmakers mined many of the appendices from "The Lord of the Rings" and Tolkien's other writings, including "The Silmarillion" and his notes.

Characters only mentioned in passing in "The Hobbit" or who never appeared until "The Lord of the Rings" have been retconned into this film, either to link the two stories in viewers' minds or to expand upon minor characters.

The first scene in The Shire shows a conversation between Bilbo and his nephew Frodo, which never appeared in the book.

Galadriel and Saruman both appear in Rivendell to meet with Elrond and Gandalf, but neither of the first two show up in Tolkien's writings until much later.

Radagast the Brown plays a much bigger role in the film than he does in the book, diverting a pack of orcs (who also don't appear in the book) with his bunny-driven sled.

And Azog only gets a passing mention in the book as the murderer of Thorin's grandfather Thror, but the film supersizes both his strength and his vendetta against the dwarves.

In Tolkien's works, Azog had already been killed 150 years before the events of "The Hobbit" by Thorin's cousin Dain.

Bilbo is also made out to be more of a hero than he is in the book. In the film, after much deliberation, he decides he wants an adventure. But in the book, Gandalf all but coerces him into joining the company.

But after Bilbo helps Gandalf defeat the trolls, the film robs Bilbo of one of his great moments. In the book, Bilbo searches through the troll hoard to find his elven blade, later named Sting.

But in the film, Gandalf hands him the sword, and practically needs to force it on him.

There will be plenty of other changes ahead in the two remaining films. Legolas makes an appearance, and it's a fair bet Beorn's role will be embellished. Gollum, whose part in the book is effectively over, will no doubt appear in the next two movies.

But remember that "The Hobbit" was retconned by Tolkien himself. After he wrote "The Lord of the Rings," Bilbo's simple magic ring had become the One Ring, and Tolkien rewrote the chapter "Riddles in the Dark," when Bilbo first finds his ring and confronts Gollum.

And if it worked for Tolkien, perhaps it will work for Jackson, too.