He’s the man who brought the Lord of the Rings trilogy to the big screen and he’s just released the final instalment of The Hobbit, but Peter Jackson could be finally finished with adapting the work of J.R.R. Tolkien.

The Hobbit Battle of the Five ArmiesThe Hobbit Battle of the Five Armies could be our last visit to Middle-earth

Speaking at a press conference in London after the world premiere of The Hobbit: The Battle of the Five Armies, the New Zealand born director said that the film was most probably his last adaptation of Tolkien’s work.

“The Tolkien estate owns the writings of Professor Tolkien. The Hobbit and The Lord of the Rings were sold by Professor Tolkien in the late 60s, the film rights,” Jackson said. “They arethe only two works of his that have ever been sold … So without the co-operation of the Tolkien Estate, there can’t be any more films.”

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Aside from The Lord of the Rings and The Hobbit, Tolkien also wrote many other tales set in Middle-earth, including the posthumously published The Silmarillion. The Silmarillion was published in 1977, four years after the author’s death and fleshed out the story of Middle-earth prior to the time of Bilbo and Frodo Baggins.

Tolkien’s son Christopher serves as the literary executor of his estate and is known to be hostile to the idea of adapting his father’s work for the screen. Speaking to Le Monde in 2012 he said, “Tolkien has become a monster, devoured by his own popularity and absorbed by the absurdity of our time.”

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“The chasm between the beauty and seriousness of the work, and what it has become, has overwhelmed me. The commercialisation has reduced the aesthetic and philosophical impact of the creation to nothing. There is only one solution for me: to turn my head away,” he added.

Tolkien previously started legal proceedings against New Line Cinema in 2008, who he claimed owed his family £80 million in unpaid royalties, the two sides later reached an undisclosed settlement, and Christopher withdrew his legal objection to the The Hobbit films.

The Hobbit Battle of the Five ArmiesWill Ian McKellen get to play Gandalf the Grey again?

However Ian McKellen, who has played Gandalf in all six of Jackson’s Tolkien adaptations, feels more optimistic about visiting Middle-earth again on the big screen. Speaking at The Battle of the Five Armies premiere, the actor said he was “not sure” the final Hobbit film will actually be "the end of the journey.