When he signed on to write this Tom Cruise super-production, Towne was no stranger to the series: Five years ago he won co-credit for the screenplay of the original by reworking the script scene by scene. But Towne came onto "Mission: Impossible 2" after a slew of other screenwriters (including William Goldman and Michael Tolkin) had failed to devise an acceptable screenplay -- and after the director, John Woo, had locked in a handful of splashy action set pieces.

"I don't have to tell you how great my trepidation was," Towne recalled the day before the film's opening. He remembered saying to Paula Wagner, who co-produced with Cruise: "My biggest fear is that I will write a script just good enough to make a really bad movie."

Luckily, he wrote a script that was good enough to make a really enjoyable movie, and earn him sole credit for the screenplay. It was Towne's idea to interlace a love duet with a quest to stop a killer virus. Another kind of biochemistry -- the kind that rages between Cruise as agent Ethan Hunt and the spellbinding Thandie Newton as an international jewel thief -- brings back those bygone days when Hollywood knew how to yoke together grit and glamour. The chases and shootouts benefit from the romantic sheen. And if director Woo's timing muffles the comedy and erotic playfulness, Towne himself is happy with the picture: "It does what it sets out to do: provide thrills, but with some feeling and sophistication."

Working on a probable blockbuster like "M:I-2" is the armchair screenwriter's equivalent of appearing on "Who Wants to Be a Millionaire." The characters are so much larger than life and the action so outlandish, at first you think it's as easy as jotting down a daydream. Then you realize how hard it is to place personalities and incidents in a narrative mesh that will engage an audience's emotions while a virtuoso action director like Woo is busy setting off cataclysmic explosions.

But Towne came to the task prepared. He has been an uncredited participant in many a Jerry Bruckheimer extravaganza (including the monster hit "Armageddon") and he's never lost touch with the popular pulse. His collaboration with Cruise, starting with his original screenplay for the misfiring "Days of Thunder," continued on "The Firm" (which Towne co-wrote), then the first "Mission: Impossible."

Towne has won a critical following for his work as a writer-director: "Personal Best" (1982) and "Without Limits" (1998). But he brings just as much commitment to collaborative tasks like "M:i-2." Interviewing him now was as full of revelations as it was when I interviewed him about "Chinatown" 27 years ago. The man breathes storytelling in all its forms; there's nothing strained or showoffy about his references. At one point he mentioned Katherine Anne Porter's short novel "Pale Horse, Pale Rider" as another work about a killer flu. Porter's heroine nearly dies from it, and she works in a couple of passages about the Kaiser spreading the flu ("It is really caused by germs brought by a German ship to Boston") that are right out of a movie like "M:I-2."

The outcome has been smooth, but the working out of this film was notoriously tough. Why?

There were a lot of writers on this movie before I came on. And at some point in that process John Woo came aboard. He had gotten very far with his action sequences. So finally, what they were left with were five or six highly developed action sequences and no story. So Tom [Cruise] and Paula [Wagner] said, "Guess what: These are the action sequences, please write the story." That was something I never had remotely attempted to do before. And it was an interesting exercise.

There were certain things that were not so difficult. Like the mountain-climbing sequence, which was originally planned for straightforward suspense. I said, "Well guys, you know, this is not 'Cliffhanger.' This should be our hero's idea of a busman's holiday. If we could, we should get Julie Andrews singing 'the hills are alive with the sound of music' or 'folderee, folderaa' -- I actually wrote that suggestion into the script! The point is he's having a good time.

And when I came on, in the opening sequence, in good "Mission Impossible" fashion, a guy was wearing a mask, and the mask was taken off, and what was revealed underneath was Dougray Scott. Well, who cares? Nobody would know who he is anyway.

You mean, the scientist we barely get to know was accompanied by a guy we don't know, who then took off his mask to reveal another guy we don't know?

That's exactly what I said.

I had seen a "60 Minutes" program in which drug companies were seen to peddle bad drugs to Third World countries, drugs they knew to be out of date or positively impotent. I thought this was a horribly immoral and frightening thing. I had mentioned this to Tom in passing and then he went his own way, since I was working on "Without Limits" and writing other projects. But he said, "That's interesting."

Do you remember reading about scientists who had been talking about the horrors of the old Spanish influenza in 1917, 1918? Katherine Anne Porter's "Pale Horse, Pale Rider" covered that. These scientists were saying that every 96 years or so there was likely to be another outbreak and we would be no more prepared now than they were then.

I read about a scientist in the '50s who tried to dig up from dead bodies some living remnant of tissue in order to make a vaccine of the old Spanish flu virus residing in that tissue. Finally in the '90s a couple of scientists went up to the frozen tundra in Alaska. They found a village where virtually all the inhabitants had been wiped out by that virus. They dug up the bodies from the tundra and found viable tissue with which they could make a vaccine -- and did. I thought this was kind of exciting, having nothing to do with any movie. It stimulated my thinking about drug companies and what they were doing. Drug companies are making less and less money because they have to make a broader variety of antibiotics because the simple sweeping antibiotics aren't as effective any more. What if they engineered both a killer virus and a vaccine to make money? From that came what you saw.

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