This sequence serves a double purpose. It arouses anxiety on the part of the viewer, because you think, "Jesus Christ, he knows what's going to happen." It also informs the audience about the minimal technical stuff Cruise is doing, so as he's doing it they can say, "Ah yes, there's the injection gun." So it's an efficient sequence, and it's fun in terms of character, and hopefully it arouses, "Oh God, the villain is ahead of the hero."

I remember vividly working out, in the first "Mission: Impossible," the disparity between what one guy says happened, what really happened and what Tom is thinking, which I thought was a more radical thing than people realized or than people commented on. I thought that little mini-narrative was pretty good. And I worked out very specifically with Tom the sequence in this film, too.

Look. Here's a script that in its final form was 84 pages -- that tells you how efficient you have to be to advance the plot. For each page there's a minute and a half of screen time. John is filling the pages with action so you have to be super-efficient. In its own way it's no less complicated than the first story. I just think you can follow this one better.

It didn't take long before I thought of Hitchcock's "Notorious".

In a strange way you have both the villains in both those pictures deeply in love with the girl and you're meant to feel that. And I love that use of a triangle.

You even have a substitute for Claude Rains' protective, suspicious mother.

Yes, that Richard Roxburgh character. And we even have a racetrack! That was not intended; it's just suddenly we had this great racetrack down there. Sure there was an echo of "Notorious." It's very rare to develop a love triangle as a subplot that happily exists and helps you advance the plot -- that's a hard thing to do. But it also, not coincidentally, gives the heroine something to do for a change. Thandie Newton actually owns part of the story.

That for me was the source of the most fun -- she really is a spellbinder, and she gets something cooking with Cruise.

There's definitely a chemistry there. You know, Thandie was Nic's idea.

Nicole Kidman?

Yeah, Tom's wife suggested Thandie. I had seen "Flirting." But what I'd seen her in that really made me fall in love with her was her screen test for the island girl in "The Firm" [which Towne co-wrote]. I liked her so much better than anybody else I said to Sydney Pollack [the director] "Why don't you cast her?" And he said, "She's too cute, too attractive." And I didn't know quite what he meant by that unless he felt she would interfere with the leading lady.

So when Tom told me, "There's this actress, Thandie Newton," I said, "Don't even think about it -- that's a great idea. Please let's do it." I was so happy. She's such a bright girl and so much fun to talk to. She's quick, she's unaffected. The other thing I really like about her is that she's from an alien culture and there's not any hint of her having been affected by racism -- at least, no hint of it that I have ever seen. In "Flirting" she's like a little queen. She doesn't know about racism, doesn't care about it and that's invaluable for a romance like this one. There's no chip on her shoulder -- no expecting to have to lash back at somebody.

She's of a piece with Ingrid Bergman in "Saratoga Trunk"; that Casey Robinson screenplay where there's one of my favorite exchanges in movies. Bergman's kicking around the Latin Quarter in New Orleans and the guy asks, "Where will you go?" And she says, "What do you care?" And he says, "You'll pardon my saying so, but you're just an extraordinarily beautiful woman." And with that, she smiles suddenly and says, "Yes -- isn't it lucky."

In that spirit, Thandie is comfortable with her own attractiveness. Not in any vain, preening way -- just, "I'm there and I know I'm attractive: next case." And that's such an attractive quality. She's not being coy about it, and not being preoccupied with it.

Somebody took me to task for having Tom tell her, "Damn, you're beautiful." The interesting thing was the original interchange was "Damn, you're beautiful." Then she said, "That's because I'm on my back." Then he spun her around and said, "I don't think so." Those last two bits were lost because we didn't get them quite right. But I don't mind our fallback position, because she is so beautiful.

Speaking of "Notorious" -- her presence is part of what suggests other Cary Grant-Hitchcock movies too, like "To Catch a Thief" with Grace Kelly and "North By Northwest" with Eva Marie Saint.

Again, it's that regal feeling.

She's also a great silent actress.

I love that moment when Tom says, "Don't turn around," and the look on her face is, "You numb-nuts." And she turns around. I love it when she says, "What are you going to do? Spank me?" She's so expressive, she does a lot by doing so little.

You talked about the challenge of putting together a script from all these existing pieces. But I also was thinking these "Mission Impossible" films force you to do a kind of writing that's absolutely atypical for you. You're a writer who draws both from the movies and from reality -- what a character does for a living and where he or she grew up are matters that inform your dialogue. Here you may know what the characters do for a living, but it's either so insulated or fantastical it doesn't really give you any help.

Yeah, a lot of my tools go out the window. You're the only person who's hit on what was one of the central writing problems. That took some working at it: to develop a language that at least had the simulacra of life -- if that's what you want to call it -- even if it wasn't real. That's what takes three drafts: to get that feeling for language, to get the right level of reality -- or its own level.

I think it works. Like when you have the guys sort of tear apart a cliché -- we rolled a snowball into hell, now we'll see if it has a chance. It doesn't call attention to itself, but there's a low-key smartness to it.

And there is an occasional metaphor: "Suppose she is sort of a Trojan horse, why deny me the pleasure of a ride or two?" And the occasional archness of Hopkins, in his speech patterns, or when he talks about the pilot who didn't make the flight he was supposed to but made it on "to the next one, in cargo, stuffed into a rather small suitcase considering his size."

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