Michelle Pfeiffer has become an evil witch.

For the past few months, she's been trying her hand at some black magic, like eating the heart of a young star, spilling unicorn's blood and turning people into billy goats just so they can pull her carriage along.

Don't worry, though -- no goats or unicorns were harmed during the making of Pfeiffer's upcoming "Stardust," which has been filming quietly over the past few months in England, Scotland and Iceland, with hardly a word coming from the set of Pfeiffer's dark doings. That was, until last Friday, when about 8,000 fantasy fans got a sneak peek at the film, which is based on a book by legendary fantasy author/graphic novelist Neil Gaiman, during a presentation from the filmmakers at Comic-Con.

"This was great," "Stardust" producer Lorenzo di Bonaventura said. "We're really showing our underwear, in a way. Some of these scenes, we just saw them for the first time three days ago, and it's really a sense of, 'Am I showing all the warts and blemishes before we've had a chance to work on it?' "

The filming of "Stardust" -- which also stars Claire Danes, Charlie Cox, Sienna Miller, Robert De Niro, Rupert Everett and Ricky Gervais -- is about three-fourths finished, but director Matthew Vaughn has been working overtime, shooting scenes with two units simultaneously, cutting as he goes.

So in many ways, the fans' first look was also a test case for its makers -- is the film working? Is Vaughn, who has mostly worked on gangster films like "Lock, Stock and Two Smoking Barrels," "Snatch" and "Layer Cake," also adept at fantasy, particularly one that's equal parts adventure, romance and whimsy? How close is the film to the world originally imagined by Gaiman? Will it win over the faithful as well as new converts?

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"They've taken what we did and developed it into a slightly different world, but it's just as full and rich and wonderful," said Charles Vess, who illustrated the original work. "Everyone [at the Comic-Con panel] was very enthusiastic. There was a lot of clapping and hooting, so I think they liked what they saw."

Gaiman and Vess' story is about a young man named Tristan (Charlie Cox) who is on a quest to retrieve a fallen star for a girl he's in love with. Unbeknownst to him, the star isn't really a "steaming leap of meteorite metal" as he supposed, but has human form as a glowing young lady (Claire Danes), who broke her leg when she fell from the sky, and is in no mood to be "dragged halfway across the world to be presented to anybody's girlfriend," as Gaiman said.

Tristran is also unaware that he's not the only one trying to steal the star: Michelle Pfeiffer's witch, Rupert Everett and his power-hungry prince brothers are also on the hunt for the star (its heart is a source of power) and are more than willing to use deadly force to get their way. "One thing I'm proud of is that our princes are more prominent characters," said screenwriter Jane Goldman. "They're not just lurking in the background, and we've got some amazing British comedians playing them."

Goldman said she was worried at first about adding a few characters that don't appear in the book, such as Gervais' Ferdy the Fence, but she was reassured by Gaiman's thumbs-up (he's been involved as a producer and had a hand in the casting the film, due March 9, 2007). "You have to choose your collaborators with great care," Gaiman said, "There were 'Sandman' scripts that arrived in the post from Warner Bros. that would leave me physically sick. I never finished reading some of them. But getting Jane Goldman as a screenwriter, getting Matthew Vaughn as a director means that I have a 'Stardust' being made I'm incredibly happy with."

"You can make an incredibly faithful adaptation, but that doesn't mean it's going to be a perfect movie, so yeah, there are things that are different, but the spirit of the book is very much there," Goldman said. "The fact is, knowing Neil is behind the movie has protected us an awful lot from the fury of Neil fans, if there was to be any. Neil's happy with it, so I think Neil's fans will be happy with it too."

For more on Neil Gaiman, check out the feature [article id="1510230"]"Weird World: Neil Gaiman Reflects on 'MirrorMask'."[/article]

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