In an article from Hero Complex, The Hobbit trilogy director Peter Jackson commented on the move to the a trilogy, aspects of the story expanded from the novel, and about designing the look of Smaug.

Highlights:
- Announcement of change to a trilogy "was announced to us the day of the wrap party" according to Martin Freeman (Bilbo).
- The Lord of the Rings appendices used to provide more of Gandalf's history, how he joined Thorin's company of dwarves and provide more story for Gollum.
- After Guillermo Del Toro left the production, "I thought, if I’m going to do it I need to actually be comfortable, to do the thing that I want to do in my head. So I suddenly found myself scrambling. I was literally scrambling to get designs ready on time for the film that I wanted to make. And we were revising the script furiously. The delay didn’t help anybody. It didn’t help him. It didn’t help us. It didn’t help the film."
- On Smaug: "The trouble with redesigning dragons is that if you really get fruity with it, it suddenly starts to look like some sort of monster from another planet — you very quickly can go into science-fiction territory. ...So I’m not trying to step away from the dragon. I just want to present the most venal, scary, decrepit, nasty dragon that I possibly can."
- "I just like to tell stories," Jackson said. "I don’t set out to try to preach to people and put hidden meaning into things. I just think if you can entertain people and give people a good time at the movies you’re doing your job well. I don’t think it’s any more complicated than that."

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