The movie was originally titled The Hobbit: There and Back Again. When the series was extended from two movies to three, the title no longer fit the tone of the final installment and it was changed to The Hobbit: Battle of the Five Armies.
"The Hobbit: The Battle of the Five Armies” brings to an epic conclusion the adventures of Bilbo Baggins, Thorin Oakenshield and the Company of Dwarves. Having reclaimed their homeland from the Dragon Smaug, the Company has unwittingly unleashed a deadly force into the world. Enraged, Smaug rains his fiery wrath down upon the defenseless men, women and children of Lake-town.Obsessed above all else with his reclaimed treasure, Thorin sacrifices friendship and honor to hoard it as Bilbo’s frantic attempts to make him see reason drive the Hobbit towards a desperate and dangerous choice. But there are even greater dangers ahead. Unseen by any but the Wizard Gandalf, the great enemy Sauron has sent forth legions of Orcs in a stealth attack upon the Lonely Mountain. As darkness converges on their escalating conflict, the races of Dwarves, Elves and Men must decide – unite or be destroyed. Bilbo finds himself fighting for his life and the lives of his friends in the epic Battle of the Five Armies, as the future of Middle-earth hangs in the balance."