THE BFG “Shit. Did I leave the stove on?”

FORGET THE DISNEY/Spielberg pedigree: The most important merger in the making of The BFG is the reunion of the director with Melissa Mathison, who wrote the screenplay for 1982's E.T. the Extra-Terrestrial. While The BFG is a faithful adaptation of the 1982 children's book by Roald Dahl, there are decided parallels between Mathison's two scripts, which each hinge on the friendship between a melancholy child and a powerful, benign nonhuman.

Mathison died in November, and while the technical necessities of The BFG are such that the bulk of it must have been finished before her death, Spielberg's film feels weirdly preservationist, as if he didn't wish to change a single one of Mathison's words, even when some quick tweaks would have fixed clunky sequences in its languid first half. It's a sensation similar to the one that came with A.I. Artificial Intelligence—which not only has a title made out of initials, but was similarly based on a mantle Spielberg picked up after the death of its originator, Stanley Kubrick.

As such, The BFG is an oddly paced but eventually rewarding film, with one or two flat-out magnificent stretches. You probably remember Dahl's book as being bubbly and bright, but the English author's humor and fluidity with language disguised a dark tale of Dickensian sorrow and Greek-god violence. Sophie is an orphan, a completely isolated (and tiny) figure in a decidedly inhospitable world. When she, in the dead of night, spies the 24-foot-tall BFG—which stands for Big Friendly Giant, although she doesn't know about the "Friendly" part just yet—outside her orphanage window, he abducts her and squirrels her away in his secret cave in Giant Country.

This would be an entirely different movie if Sophie and the BFG didn't become friends, but they do, of course, and the movie gets great mileage out of the soft, kindly, and computer-enhanced performance of Mark Rylance as the BFG. He's not scary-looking, but he's strange in a way that feels true to Dahl's penchant for grotesquerie, and his half-made-up version of English never sounds like gobbledygook. Unlike Giant Country's other citizens, who are twice as tall and munch up children like popcorn, the BFG lives in peace, growing terrible-tasting snozzcumbers, drinking downward-fizzing frobscottle, and letting out tremendous, uh, "whizzpoppers." Every day he catches and catalogs dreams, and at night he blows them into the windows of sleeping children.

As slow as the first half of The BFG is, Spielberg and Mathison get much more right than wrong, allowing large chunks of this world to remain in the realm of mystery, and never over-explicating every strange and wondrous thing on screen. The scene in which the BFG brings Sophie to the land of dreams is weird and beautiful and trippy and magical; also handled magnificently is a sequence involving the Queen of England, played by the perfect Penelope Wilton. The less said about it the better, but it's fantastic, and involves whizzpopping corgis. I've already said too much.

Which makes the less successful stretches of The BFG all the more frustrating. It takes an incredibly long time for the thing to get going, and the other, larger giants barely seem to register other than as part of a manufactured threat to provide some semblance of conflict.

But what's great is really great, and Spielberg seems to have once again tapped that particular vein of childhood logic where strange things are to be explored and experienced rather than feared. For certain patient kids, the movie version of The BFG will be a source of delight. The rest of us should be so lucky.