THE TAKING OF Flight 847: The Uli Derickson Story is two hours of hell . . . and a hell of a movie. I'm sure there's a temptation to dismiss it as just another off-the-headlines TV docudrama that aspires to distill a real-life event that most viewers only remember enough to know that it happened but not nearly well enough to quibble about details. Resist that temptation. This is a movie with pace, drama and integrity, gripping and true to its subject in all the ways that count.

The NBC movie is based on the infamous June 14, 1985, hijacking of TWA Flight 847, its 153 passengers and crew on a routine flight from Athens to Rome. The hijacking was carried out by two Lebanese terrorists who were later joined by a dozen others as the jet flew back and forth between Beirut and Algiers and the rest of the world tried to figure out what to do about it. Several of the American men on board were savagely beaten and one, U.S. Navy diver Robert Stethem, was murdered.

When the 17-day ordeal finally ended, passengers and crew praised TWA purser Uli Derickson for her composure and bravery. The Czechoslovakia-born Derickson is fluent in German, which one of the hijackers spoke, too, so she became the liaison between captives and captors. Derickson even managed to secure the release of several men, women and children, and tried to keep the identities of the Jewish passengers a secret from the terrorists.

The Taking of Flight 847, which stars Lindsay Wagner, who gives a special performance as Derickson, is based on her story as told to Jim Calio, then a writer for People magazine, who was co-executive producer.

THE BEST stories are about ordinary people caught up in extraordinary circumstances and that's something The Taking of Flight 847 never loses sight of. Derickson didn't intend to be heroic and probably still doesn't think of herself that way. Most of the time she's plenty terrified and shows it.

But that ability to work through fear -- to dominate it instead of letting it dominate you -- is what defines bravery. Given the horrible circumstances in which she finds herself, Derickson does the best she can because that's all she can do.

Too, sometimes how we react in hard times has to do not with bravery, but with which of our fears is the strongest. When the hijackers order Derickson to identity the Jewish passengers, she refuses for a reason that is not as obvious as you might think.

All the compassion one human being can feel for another is at work within her, of course, but there's something more subtle going on, too. Uli Derickson is German, and it's the terrible weight of her nation's recent history that keeps her from doing what she's told.

For her, there's simply no choice. As she tells the hijackers, ''I can't do that.''

Something else The Taking of Flight 847 does awfully well is show how what passes for logic and reason in one culture may be irrelevant in another. The hijackers stop beating their captives long enough to pray toward Mecca. They commit murder, yet they're tender and solicitous toward a pregnant passenger.

It's no small achievement that the hijackers come across as flesh-and-blood human beings. They aren't sympathetic, but they are understandable, at least according to their own culture and circumstances. That's mostly due to a wonderful performance by Eli Danker as the hijackers' leader, a Hezbollah Muslim who calls himself Castro. He brings shadings, colors and motives to a man engaged in barbarism. Ironically, Danker is an ex-Israeli paratrooper.

In one long scene, Danker and Wagner sit side by side on the jet. They talk, he asks her to sing a popular German song called Heimatlos, or ''without a country.'' And they talk a little more, mostly of small things.

To us and to Uli Derickson, the man is a butcher and a fanatic. To himself, he is a patriot. It's a terrific scene full of fear and tension as a kind of tentative psychic-emotional link joins the terrorist and his captive. This man is doing what he's doing for reasons that seem clear to him however obscure, terrible and unjustifiable they are to the rest of the world.