Who's the king of the jungle?

Deep in the jungle something is stirring. Two awesome beasts are sizing each other up as they prepare to fight to the death. Only one will emerge the winner and take the title of Christmas box-office champion.

Their battle will be more ferocious and stomach-turning than anything those TV jungle celebrities are suffering. A Bushtucker trial looks like a vicar's tea party compared to the dual as King Kong takes on The Chronicles Of Narnia: The Lion, The Witch And The Wardrobe.

At stake are millions of dollars and global domination. The only certain winner is New Zealand. Both movies were shot there, boosting the country's film industry kick-started by The Lord Of The Rings trilogy.

In one corner of the jungle clearing is a large silverback gorilla standing 25ft tall and weighing 8,000lbs. In the other is the proud lion king - Aslan, the Christ-like leader of Narnia.

Both highly-anticipated, big budget blockbuster movies premiere in London next month within days of each other. They have other things in common - New Zealand born directors, the same creature-creating special effects company and the same desire to thrill cinema audiences around the world.

Both are deeply personal projects too. Director Andrew Adamson, who introduced filmgoers to the jolly green ogre in Shrek and Shrek 2, has been fascinated by CS Lewis's Narnia books since reading them as an eight-year-old. "I read all seven books continuously over a period of a year or two, just read them over and over. I basically existed in this world of Narnia for a time," recalls the US-based film-maker.

"I remembered it as this huge, vivid story with a massive battle between good and evil and a whole menagerie of mythological creatures - and I wanted the chance to bring that world to the screen."

Five years ago, it wouldn't have been possible to put a photo-real Aslan on screen. As well as a computer-generated lion, three life-size animatronic puppets were made for key sequences. They included an 8ft puppet with radio-controlled head and another "riding version" for scenes in which the children ride on the animal's back.

Howard Berger, responsible for special make-up and creatures, reports much debate about the size of Aslan. "Originally, he was going to be a lot bigger," he says. "We created a larger one but it was almost like a dinosaur. We were concerned it might upset the kids. So we scaled him down."

Young actors Anna Popplewell and Georgie Henley didn't see the "dead" Aslan lying on the Stone Table until the scene was shot. "I remember Andrew was always very, very careful about what we showed the girls, or any of the kids," recalls Berger.

'Aslan was something we never showed Georgie or Anna for months, until that day came. I went in early and placed the lion there, and Andrew had all the cameras ready.

"We let the girls come in and ran cameras as they entered. All that emotion was real. They became very attached to it. We never wanted them to think of it as a puppet, that we would drag in and drop down. It was all very real for them."

Similar thinking ran through the mind of director Peter Jackson as he prepared his remake of King Kong, a project dear to his heart that's been a dream for many years. Like Adamson, he was first affected by the story of the beauty and the beast as a youngster.

Seeing the 1933 original was the reason he wanted to become a film-maker. "It's inspired me, it's informed my approach to film-making and cultivated my love of fantasy and horror. It's a hugely important film for me," he says. At the age of 12, he produced his own version of King Kong using his mother's old stole for the animal's fur and a painted cardboard model of the Empire State Building, which the gorilla climbs at the movie's climax.

Jackson's home movie version was never completed, just as his big budget remake was nearly never made. The director of Heavenly Creatures and Bad Taste was six months into pre-production of King Kong in 1996 when the studio backing the movie called a halt. Nine years later, executives had second thoughts, awarding him the best directing deal in history - $20m up front against 20 per cent of the gross.

The change was motivated by Jackson's ground-breaking trilogy The Lord Of The Rings. The figures - $3bn earned worldwide and 17 Oscars, including one for best picture - made him the most bankable film-maker in the world.

Displaying a degree of nervousness as he walks along the red carpet at the premiere would be perfectly understandable. King Kong means a lot to him. "My hope for the movie is that it'll be everything that I love about the original," he says.

There's been no shortage of Kong movies over the years, although none has matched the original. A sequel, Son Of Kong, passed without notice. The 1976 King Kong remake, starring Jessica Lange and Jeff Bridges, flopped. Possibly the problem was the gorilla himself. A fully-articulate 40ft ape failed to work, so the makers resorted to a man in a monkey suit.

Despite that failure, a sequel called King Kong Lives showed up a decade later and met with a similar fate.

Like the makers of Narnia, Jackson was concerned that the leading creature wasn't just an impressive special effect but a beast with a heart. The lessons learnt on The Lord Of The Rings - that the more fantastical the story, the more it should be grounded in reality - were applied and the 1996 King Kong script rewritten to take that into account.

"The original is my favourite movie of all time. And I guess for that reason, I wanted to remake it," he says. "I just thought a version told with the technology that we have available to us today would be a really amazing thing. So I guess I'm remaking King Kong as a fan who wants to see a high-tech version of this wonderful story."

He certainly talks about the creature as if he's real. "We assumed that Kong is the last surviving member of his species, the last of the huge gorillas that live on Skull Island," he says. "He's a very lonely creature, absolutely solitary. Every day, he has to battle for his survival against very formidable dinosaurs on the island. I'm imagining he's probably 100 to 120 years old by the time our story begins. And he's never felt a single bit of empathy for another living creature in his long life; it's been a brutal life he's lived."

The gorilla was always going to be computer-generated but to make Kong act, he turned to Andy Serkis, the British performer who "played" Gollum in The Lord Of The Rings. That character was created using motion capture - first filming Serkis acting the role, then rendering Gollum as an artificial digital character. Kong was created in much the same way, although on a bigger scale, with Serkis providing the template for the gorilla's emotional reactions.

The reaction he couldn't guess was that of cinemagoers faced with a choice between King Kong and Aslan. This is one rumble in the jungle that's impossible to predict.

* The Chronicles Of Narnia: The Lion, The Witch And The Wardrobe opens in cinemas on December 7 and King Kong on December 15.