Although Depp didn't answer questions, the crowd screamed and cheered when the actor was onstage, the room filling with flashes of cameras.
The shocking addition of Depp to the stage was a great end to the panel discussion, which began with filmmaker Tim Burton getting cheers of his own from the crowd. In a presentation that included a teaser trailer of various footage from the film in 3-D, Burton laughed about all the wacky characters who populate the world of his version of "Alice in Wonderland," including the Mad Hatter, played by Depp; the Red Queen, played by Helena Bonham Carter; and the White Queen, played by Anne Hathaway.
"Looks like a freak show, doesn't it?" the director laughed while the character images graced the screen.
Burton said the "Alice in Wonderland" film doesn't stick exactly to the book by Lewis Carroll, but instead takes the characters and various scenes from the book and molds them into an updated story.
"It's all based on [the book]," he said. "This material's seen a lot of film versions of it — we tried to take all the elements of it and weaved it into a story that had some motion to it and emotion to it, and not just a series of events."
Burton said the Jabberwocky poem from the book played a part in the movie, although not every piece of the work is used. "We don't use every character, but we tried to make all the material new while being true to it as well," he said.
Before Depp entered the stage, Burton said the actor "had a hand" in picking out his costume for the Mad Hatter role. "He's the type of actor that a lot of the character comes from the look of the outfit," he said. "It helps him really create and get into who the character is."
The footage showed everyone from Stephen Fry's Cheshire Cat — which was so creepy that Burton said, "This confirms my hatred of cats" — to images of Alice shrinking. It ended with Alice saying, "That's impossible," to which the Mad Hatter replies, "Only if you believe it is."
Burton said the movie combines several types of movie technology to arrive at its unique style, although very little stop-motion animation ended up being used.
"There are a lot of different ways to do things, and we sort of mixed them all together," he said. "It's mostly animation and having the actors do things their own ways."
During the question-and-answer portion of the panel, Burton was asked which of his films is his favorite. " '[Edward] Scissorhands' is important to me. It's special and had some thematic things," he said of the film that also starred Johnny Depp as the title character. "I like bits and pieces of all of them. I don't watch them after I do them, but they're all special in different ways."
Another fan asked what the hardest part of making "Alice in Wonderland" was. "Being here when it's not done — I have this sort of white-rabbit-with-a-ticking-clock where I need to be doing it," he said. "Just combining all the weird elements, I'd say this is the most difficult one so far."
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