I cannot read, or hear, the final pages of E.B. White's "Charlotte's Web" without breaking down in tears. The famous last line is perfection: "It is not often that someone comes along who is a true friend and a good writer. Charlotte was both." And on the chance that you don't already know the book, I can tell you that Charlotte is a spider, Charlotte A. Cavatica (look it up). Had she not been, the line would have lost its power. But the book is not, of course, about spiders; well, yes it is, but it is more about the power of words, the magical power that feeds our imaginations and gives meaning to the way we frame the thoughts and acts of our lives. It is the story of how, by making a little pig famous, Charlotte saves his life and gives meaning to ours. That's quite a burden, but White carries it off easily.

So the question is, how does one film a classic? It's not possible, by definition, to add to it, to make it better. It's already 100 on a scale of 1 to 100, so it cannot be made bigger, more accessible, more - well - obvious; in fact anything done to help visualize it will only diminish the magic of creating, or re-creating, its world inside our imaginations. Is it possible to be faithful to perfection? Obviously not. But it is sometimes possible to leave it alone enough that the greatness will still come through. And although this version of "Charlotte's Web" flirts with disaster, it still manages to keep enough of the genius that we who know and love the book can leave the theatre relieved rather than angry or depressed.

Young Fern (Dakota Fanning, almost too old for the part) saves a runt pig named Wilbur from being killed, and is allowed to keep him at her aunt and uncle's farm across the road, where he meets Charlotte (voiced by a calm and comforting and deliberate Julia Roberts) and a barnful of other animals, including Templeton the rat (the voice of Steve Buscemi). As Wilbur grows, that first year, he's threatened with having his life ended in the smoke house, a building very visible near the barn. Charlotte determines to save his life by pointing out his important features, so one night she weaves into her web the words 'some pig.' Voila; instant celebrity.

Let me assure you that this is not some simple-minded cartoon version of the story; it uses sophisticated computer-generated magic, if you will, to animate a real spider and make believable what would otherwise be deadly. The same is true for the other animals in the barn, though the attempt to give each of them cute lines to define them (they are voiced by famous names, including John Cleese, Oprah Winfrey, Cedric the Entertainer, Robert Redford and others) diminishes their value to the story. But the film never veers too far from Charlotte, trying to think up new words for Wilbur, nor from Templeton, who redeems himself in a brilliant stroke by finding the perfect word in a torn page from a Racing Form.

So why, in a story about a pig and a spider, do we cry? Because White - who retired early from The New Yorker to his farm in Brooklin, Maine - is telling us the story of birth, life and the death that will come to all of us. Because Charlotte, as winter nears and she spins her egg sac with its 546 eggs ("This is my magnum opus," she says), must die in order that her children shall live; she cannot live forever except in the memories of those who live after her. It is not enough, and it is enough.