Directed and co-written, with Peter Baynham, by Sarah Smith, “Arthur Christmas” unveils* the secret of how Santa manages to deliver presents to every child in the world in one night.

    The latest in a long ancestral line of Santas, voiced by Jim Broadbent, nears retirement* and will soon hand the job over to one of his sons.

    Sporting a fir-tree-shaped goatee*, firstborn Steve (Hugh Laurie, vocals) runs the annual task like a military operation, overseeing the mighty “S-1,” a two-mile-long spaceship (vaguely sleigh*-shaped) from which a million present-delivering elves* descend and deliver. Typical of the throwaway details, we hear a computer voice announce in passing: “Converting* milk and cookies into biofuel*.”

    The film’s heart belongs to the younger son, Arthur, voiced sweetly by James McAvoy. This fellow, eager to impress his father, cherishes the Christmas holiday and corresponds* warmly with “Dear Santa” letter writers around the globe.

    Crisis: This year a little girl in Cornwall has been overlooked*. It’s up to Arthur, his 136-year-old “Grandsanta” (Bill Nighy, funnier than his material) and their long-mothballed traditional sleigh and reindeer to place a pink bicycle under the girl’s tree in time for Christmas morning.

    In its espionage* and secret-mission trappings, “Arthur Christmas” occasionally brings back memories of “Cars 2,” which are not warm memories. But only occasionally.

    There’s a wonderful supporting character along for Arthur’s magic dust-fueled ride, a “wrapping operative” with an eyebrow piercing named Bryony (Ashley Jensen). This elf lives to gift-wrap, and the way she takes care of present-packaging and taping duties under extreme* duress and time limits becomes a lesson in supporting a one-joke character.

    Even when its storyline focuses on sibling rivalry* or competing methods of yuletide* maintenance, “Arthur Christmas” has the class not to become constant bickering*.

    (SD-Agencies)