Peter Jackson has announced that the third and final film in his adaptation of The Hobbit will now be called The Hobbit: The Battle of the Five Armies. Meanwhile the old title, There and Back Again, will be used as a possible alternative name for all three films.
Posting on his Facebook page, Jackson reasoned,
“There and Back Again” felt like the right name for the second of a two film telling of the quest to reclaim Erebor, when Bilbo’s arrival there, and departure, were both contained within the second film. But with three movies, it suddenly felt misplaced—after all, Bilbo has already arrived ‘there’ in the “Desolation of Smaug”.
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As Professor Tolkien intended, “There and Back Again” encompasses Bilbo’s entire adventure, so don’t be surprised if you see it used on a future box-set of all three movies.