Extra story drawn upon in ‘The Hobbit’ trilogy

You may be wondering how "The Hobbit" can be stretched into an entire trilogy of films -- a plan director Peter Jackson confirmed on Monday. The film version is based on one book, after all.

But Jackson, who Yahoo! Movies recently saw at Comic-Con, foreshadowed Monday's news as he explained that he is drawing upon source material written by J.R.R. Tolkien -- material that was never published in the original book.

"There [are] other parts of the story we want to tell that we haven't had a chance to tell yet," he said.

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Jackson justified the then imminent move to make three films: "We have incredible source material with the appendices. Because 'The Hobbit' is obviously the novel, but then we also have the rights to use 125 pages of additional notes that... expanded the world of 'The Hobbit' that's published at the end of 'Return of the King.'"

Jackson provided further explanation on Monday in a Facebook post, arguing that the extra story material he is drawing upon may forever be kept under wraps if he doesn't use it now: "We know how much of the story of Bilbo Baggins, the Wizard Gandalf, the Dwarves of Erebor, the rise of the Necromancer, and the Battle of Dol Guldur will remain untold if we do not take this chance."

[Related: Comic-Con 2012: Peter Jackson reveals new footage from 'The Hobbit']

Indeed, given that Jackson's "Lord of the Rings" franchise made so much money at the box office, all three movies grossing more than $1 billion, Warner Bros. is undoubtedly seeing dollar signs.

Saying that the duo of "Hobbit" films has now turned into three, Jackson added in his post, "It has been an unexpected journey indeed, and in the words of Professor Tolkien himself, 'a tale that grew in the telling.'"

The first installment, "The Hobbit: An Unexpected Journey," which is a prequel to "LOTR," lands in theaters December 14.

'The Hobbit' Announcement Trailer

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