Many commentators have reacted harshly. The Playlist's Oliver Lyttelton wrote Jackson an open letter denouncing the decision, which he called "potentially disastrous," arguing that further dividing a story originally planned for two movies was likely to sap the plot of narrative tension. And Dorothy Pomerantz, over at Forbes, chalked the whole thing up to greed on the part of the studio.
Both compared the announcement to similar splices by the makers of the final installments of "Harry Potter," "Twilight" and "The Hunger Games" -- a bad omen for the follow-up to a series that won 17 out of the 30 Academy Awards for which it was nominated. The decision to make "The Hobbit" into a trilogy was especially perplexing considering that the 1937 book is far shorter than "Harry Potter and the Deathly Hallows" or "Breaking Dawn."
The trifurcation has even upset diehard fans of the "Lord of the Rings" series, who you might think would be eager to get as much Tolkien as they can.
Take Corey Olsen, author of the forthcoming book "Exploring J.R.R. Tolkien's The Hobbit." He's been defending Jackson's decision to make "The Hobbit" into two movies for months.
"The thing that people don't realize or think about is that there's much more material than just the pages of 'The Hobbit,'" Olsen told the Huffington Post. "They're not stretching two films out of the 200 pages of the 1937 children's book and adding their own stuff. They're drawing on work that Tolkien did over the course of decades."
Olsen cited a great deal of "Hobbit"-related material in the appendices of "The Return of the King" and the late short story "The Quest for Erebor" as fruitful sources for Jackson's movies, and ample justification for the two films that had originally been planned. But Olsen said he was less confident that there was enough to make three movies.
"I hope that the tightness of the storytelling of the films isn't going to suffer from the luxury of being able to spill over and use a lot more time," Olsen said. "As a Tolkien scholar, I feel like they're going about the storytelling in the right way, and I hope that they're not going to undermine that by padding things to make it longer."
On the other hand, English professor Thomas Leitch, who wrote a study of book-to-film adaptations, noted that Jackson is far from the first person to spin hours of film out of a meager literary source.
"Lots of movies have been based on short stories. There the imperative is not to compress, but to expand," Leitch told The Huffington Post. "And look at a series like 'Dexter,' which makes a novel into a whole season of TV. If books can generate whole TV series, why can't they generate multiple movies?"
Even if we give Jackson the benefit of the doubt and assume his decision to make three movies was propelled by artistic concerns, his financiers must be thinking about how the trilogy will affect their bottom line. Needham & Co. media analyst Laura Martin said that she suspected "The Hobbit" producer Warner Bros. is eager to build a dependable new franchise property now that its "Dark Knight" and "Harry Potter" cash cows are depleted. But right now, she said, it's too early to say whether "The Hobbit" will pick up that slack.
"We'll know the value of the franchise after we see the release of the first movie in December," Martin said. "If it does well, it will be a really good thing that they made both other movies, because they'll be tripling the revenue. On the other hand, it's also a risk, because it costs $50 million to release a film of that stature."
"I think Warner Bros. is the best creator of content on earth, bar none," Martin continued. "But it's a hard thing to do. No matter how good you are, the content business is incredibly tough. It's hard to sit here and say whether or not 'The Hobbit' will be a successful franchise."
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