“Cowboys and Aliens” and “Arthur Christmas” seem about as different as two movies can be. The former (not among the 97 scores deemed Oscar-eligible by the Acad) is a live-action Western and space invaders mash-up; the latter, an animated holiday pic for kids.

But Harry Gregson-Williams scored both, and while he acknowledges their differences, he also found points of thematic tangency in them.

“My first ports-of-call were the central characters,” the composer says. “Both are chasing something, and they don’t stop until they’ve got it. Also, both are honest about themselves and their surroundings.”

Each score uses full orchestra and choir, but things diverge from there. “A lot of ‘Arthur Christmas’ is a personal story,” Gregson-Williams notes. “I used a clarinet and piano backed by the orchestra quite often, and that seemed to suit his character.

“?’Cowboys and Aliens’ had guitars involved, because we had to nod to the musical conventions of the Western. I also tried to suit the rugged nature of Daniel Craig’s character and give the music an outdoorsy quality.”

Any rules were Gregson-Williams’ own. “For ‘Arthur Christmas,’ I thought there’s no reason for it not to be organically orchestral, with various solo instruments,” he says. “There was no need for it to be synthetic. But ‘Cowboys and Aliens’ could be anything. It has a familiar sound to start, but with the arrival of aliens, all bets are off.”

The result blends electronic pulses and guitar riffs with moody, noir-ish figures and the expansive gestures typical of sci-fi music.

Determining how to render Christmas proved more of a challenge. “What is a Christmas sound?” Gregson-Williams asks. “Something that sparkles or uses tubular bells, perhaps. But harmonically? To me, it’s a natural place, and that’s where I went.”

Its warmhearted nature notwithstanding, “Arthur Christmas” is more than a simple tale of affirmation. The scope of its story — Santa’s ability to deliver gifts throughout the world on a single night — requires the sort of broad musical brush strokes characteristic of a “bigger” film.

“It was necessary to give the music some epic feel,” Gregson-Williams concedes, “because what’s depicted is a global operation. Yet there’s a personal story within that epic story.”

Eye on the Oscars: Song & Score
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