- Acting for Two:
- Dyeing for Your Art: Benedict Cumberbatch, in his own words, "ripped into [his] vocal cords quite literally, [he] had blood at the end of the day from tearing [his] throat to pieces." in order to get Smaug's voice right. The crew had to make a lot of "Gollum Juice" for him, a tea of honey, lemon and ginger, which Andy Serkis had created during the original trilogy when voicing Gollum.
- Enforced Method Acting:
- The fish that were dumped into the barrels to hide Bilbo and the Dwarves were real fish, with a few rubber props mixed in. At one point, Adam Brown (Ori) had as much as four hundred pounds of fish dumped directly on him. Brown hates fish, and had to fight his own phobia while buried in them in the barrel, and while he waited for crew members to pull them off of him. Since the fish were slippery, they had to be taken out by hand one at a time.
- The actors playing Bard's kids weren't told where exactly the Last Black Arrow was hidden, so their reaction to Bard just whipping it out of its Hidden in Plain Sight spot was genuine.
- Meaningful Release Date: The movie was released in China on February 21 2014. In numbers without the year, the date will be 221. In Sherlock, Benedict Cumberbatch and Martin Freeman live at 221B Baker Street.
- Missing Trailer Scene: In most of the advertising and in all three main trailers, this shot of Azog◊ was prominently featured. For reasons that still aren't exactly clear, during re-shoots it was changed to Bolg. Doubles as What Could Have Been because had they kept it Azog, we could have had a fight scene between Legolas and Azog.
- Promoted Fanboy: Evangeline Lilly and Stephen Colbert were long-time Tolkien fans before getting roles in the series.
- Real-Life Relative: Peter Jackson's daughter Katie is the barmaid serving Thorin and Gandalf at the Prancing Pony.
- Refitted for Sequel: The barrel fight scene is very similar to a scene from The Lord of the Rings where the Fellowship are ambushed by Orc archers while they're rowing through the rapids of Sarn Gebir on the Great River Anduin. The scene got cut from the film adaptation of The Fellowship of the Ring because the set where it would have been filmed wound up getting destroyed during a flood.
- Throw It In!: Richard Armitage really hated doing action scenes in Thorin's heavy cloak, and begged Jackson to have him lose it somehow. Thus, Thorin shrugging it off after it's set on fire by Smaug.
- What Could Have Been: See subpage.
- Writing by the Seat of Your Pants: Much of the Dwarves vs. Smaug scene at the end was filmed without any real idea of what they were trying to represent, because the decision had been made to make three films instead of two and they suddenly needed a cliffhanger. Only after shooting a lot of reaction shots and running around did Peter Jackson have the idea of them using the foundries to try to smother Smaug in gold.
Trivia / The Hobbit: The Desolation of Smaug