Unlike his character in "The Water Horse," 13-year-old Alex Etel from Manchester, England, likes to have fun.

In the film - based on the book written by Dick King-Smith and set to open tomorrow - Etel plays the lead character of Angus MacMorrow, a glum 11-year-old living in Scotland during WWII.

His father has been on the battlefront for years, and he lives with his mother and sister in an old and empty home, somberly awaiting his father's return.

"It's quite hard getting into it because it's such a sad, depressed kind of role," Etel said.

But Etel's character learns to lighten up after stumbling upon a strange creature - resembling the cross of a horse and a seal - which happens to be an ancient Scottish legend brought to life with the hatch of an egg. Angus takes the creature under his wing and names it Crusoe.

Crusoe begins to grow at a ferocious rate, as does Angus' understanding and acceptance of the reality of life, war and death. Angus' relationship with Crusoe forces him to cope with truth.

"It helps him because obviously his dad is gone off to war," Etel said. "Crusoe fills the position of his dad. In the end, he has to let both of them go."

For five months during filming, Etel lived and worked in New Zealand, the site chosen by director Jay Russell and production designer Tony Burrough for its varied landscape and resemblance to the mid-1900s Scottish countryside.

The production crew spent three weeks filming across the lake from Queenstown at the beginning of winter.

Aside from the cold temperatures, Etel enjoyed filming the water scenes most.

"I had to learn how to scuba dive to help me underwater," he said. "My favorite part of the movie to watch was all the underwater things. They only showed me the basic parts of those scenes. I didn't see the whole thing until I watched it."

Etel did all of his stunts, he confirmed with a self-assured smile.

"There must have been more stunt people on the set than anyone else," he said.

The harnessed back-flip is his most memorable stunt.

"That wasn't actually in the movie," Etel said. "That was in my spare time. I'm a stunt man in my spare time."

Since there are no water horses known to man, the film relied heavily on special effects.

Weta Digital and Weta Workshop - New Zealand's premier visual effects companies responsible for work in the "Lord of the Rings" trilogy, "King Kong" and "The Chronicles of Narnia" - brought Crusoe to life. Unfortunately for a young boy, working with special effects isn't as cool as it looks.

"It's a challenge," Etel said. "Sometimes you're working with a puppet, and sometimes you're talking to a tennis ball on a stick."

With a little preparation, acting to inanimate objects became natural in no time.

"You have to get over self-consciousness," he said. "You're in front of 200 people, in front of a camera, as well trying to play the part."

After Crusoe grows to the size of an obese whale, Angus must learn to let go. To get into character, Etel evoked emotion from memories of his former pet rabbit, Fluffy. After embarking on a school trip to Wales, Etel returned to face tragedy.

"Before I went, my rabbit was perfectly healthy, but when I came back it had died," he said.

His grandfather broke the news and told him Etel's mother had been the only one in the house.

"I've got suspicion of what she might have done," he said half-serious before breaking into a chuckle.

Russell chose Etel for the role after watching 750 potential Angus hopefuls.

He had his eye on Etel after watching him in "Millions," his first acting role at age 8.

"He said that he cried at the end of 'Millions,' " Etel said. "I think that stood out in his mind a bit."

As the lead in "Millions," Etel played a 7-year-old boy who stumbles upon a bag of pounds days before the currency switches to the euro. His acting career began just as haphazardly.

"I was just lucky because a casting crew came around to my old school and said if you want to audition you can," Etel said.

"I was in the right place at the right time." *