BRISBANE, Australia - In creating the Darwinian denizens that feed in the planetary night of the science fiction space thriller Pitch Black, special-effects creature maker John Cox faced some very special challenges.

"Eighty percent of the movie occurs in total darkness," said the Brisbane, Queensland-based Cox. "This gave the aliens a special look, breaking some really new ground for science fiction."

The survivors then learn the planet is about to enter a once-every-60-year period of darkness, a time when nocturnal subterranean species come to the surface to feed.

"These aliens don't have a natural vicious streak, they're just animals who're hungry," Cox said. "If one of their own kind gets in the way, even they'll be up for dinner."

Faced with such a strong biological imperative, the space travelers' most pressing priority is to stay alive and get rescued.

I don't think we're in Sydney any more.

Darwin's nightmares

For Cox, the film's central "eat-or-be-eaten" theme made developing the creatures an exciting challenge.

"We had to think through all the evolutionary and physiologic concerns these creatures would need to establish their niche and survive on such a planet," Cox said.

"There were some design changes we had to make to the creatures because evolution wouldn't have allowed it."

Cox, who won an Academy Award in 1995 for his animatronic special effects work on the farm fable Babe, says science fiction allows his imagination to run free.

"Science fiction is right up there among my favorite projects to work on, because it allows you to break out of doing exact realism with existing creatures," he said. "Instead, you're in a world of make-believe, and you have to make that real."

Pitch Black stars Vin Diesel (Saving Private Ryan, The Iron Giant) and the Sci Fi Channel's Claudia Black (Farscape). The outdoor scenes were filmed in the empty desert around Coober Pedy, South Australia, and at Warner Roadshow Studios in Queensland.

Puppets, not robots

Cox said director David Twohy (The Arrival), had a very clear idea of the atmospheric and creature effects he wanted.

The result is a moody film on a par with the classic Sigourney Weaver Alien series in setting a whole new tone for science fiction.

"David had very specific guidelines about what he wanted, which made it much easier for me to do my job," Cox said. "He didn't want any complicated, computer-driven monsters, he wanted something simpler that could be operated by hand, or directly by cable."

The result was a creature roughly 9.8 feet (3 meters) long, 8.2 feet (2.5 meters) high, with wings spanning 13.1 feet (4 meters).

In one of the most challenging scenes for Cox and others in the special-effects crew, five of the creatures run down a canyon wall fighting among themselves, with dead ones pushed over a cliff face. Others fall dead from the sky.

Through the right color filter, Australia can look quite unearthly.

"Extraordinarily creepy"

As part of the production, Cox built 11 aliens for the more than 200 visual-effects scenes in the movie, enhanced by significant amounts of digital special effects done by Double Negative Ltd.

"When you see the creatures, you'll see the design is really bizarre and unlike anything ever done before," he said. "They're very slender, with slender wrists and long arms and slender necks -- and as such, it was very difficult to conceal all the cables and other devices inside."

For Cox, even after a 17-year career making inanimate special-effect objects for films, the realism on the set of Pitch Black was enough to give him the shivers.

"It was extraordinarily creepy working in the studio, which was always completely black with only a few specks of light," he said. "And these creatures...."

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