The single most disturbing moment in all of the movies David Fincher has directed comes halfway through "Zodiac," his obsessive epic about the search for the serial killer who terrorized San Francisco in the 1970s.

The single most disturbing moment in all of the movies David Fincher has directed comes halfway through "Zodiac," his obsessive epic about the search for the serial killer who terrorized San Francisco in the 1970s.

While chasing one of the leads that flooded the city's police department, three detectives interrogate Arthur Leigh Allen (played by John Carroll Lynch), whose name came up during their tangled investigation.

Two minutes into the conversation, the officers realize the unremarkable man sitting across the table may well be their culprit. And when the suspect realizes what the detectives are thinking, he pre-empts them by saying, "I'm not the Zodiac — and if I was, I certainly wouldn't tell you."

What makes the scene so unnerving, what ties your stomach into a knot and makes you hold your breath, is that Fincher focuses on what the detectives are thinking instead of making the suspect seem scary. No ominous score, no creepy shadows, no stylized angles.

What's frightening is the way Arthur casually crosses his legs or plays with his wristwatch or talks in the flat monotone he might also use to order lunch.

"That scene was really about the notion that somebody this seemingly average could be the person keeping this terror stranglehold on an entire community," Fincher says. "He seems playful and remorseless about it, and that is blood curdling.

"The stabbing in Lake Berryessa near the beginning of 'Zodiac' is also incredibly disturbing, because it is so banal. It takes place in daylight, there is not a full moon, and there is no fog coming in over the moors. And then all of a sudden there's this weirdo standing there, this guy in a costume, and things get much worse than you could possibly imagine. But the two scenes are disturbing for very different reasons."

"The Girl with the Dragon Tattoo," Fincher's eagerly awaited adaptation of Stieg Larsson's blockbuster novel, plays both of these creepy notes — as well as a few new ones. The movie stars Rooney Mara as Lisbeth Salander, the tattooed computer hacker who helps a disgraced journalist, Mikael Blomkvist, investigate a 40-year old crime.

The book was previously adapted in its native Sweden to much acclaim by director Niels Arden Oplev. That movie made a star out of Noomi Rapace, who played Lisbeth, and grossed $104 million worldwide — which is less than the budget on Fincher's version.

"This movie cost eight times what the Swedish movie cost," says Fincher, who graduated from Ashland High School. "That is not to say that the way we executed it was worth more than the way (Oplev) executed it. This is just what I needed to do, what I thought I could do well with this story. 'The Social Network' was, for me, a very inexpensive movie. But we still spent more money than any of the other movies nominated for an Academy Award last year.

"The way I work is just more expensive than the way other people work. It is not a matter of me crossing my arms and holding my breath until I get my way, though. I can usually make a good case as to why. I shoot more days. But I also shoot with less toys. I am afforded a kind of independence by the studios that a lot of independent filmmakers would like to have. But there are concessions. You have to put all the money on the screen."

Fincher is the most successful Hollywood filmmaker to emerge from the TV commercial and music video arena (Madonna's "Express Yourself" and George Michael's "Freedom" are two of his best-known clips). "The Girl with the Dragon Tattoo" is the ninth movie he has directed: His previous films, which also include "Fight Club," "Seven," "The Curious Case of Benjamin Button" and "Panic Room," have earned $1.5 billion and worked their way into popular culture ("What's in the box?")

He has been nominated twice for a Best Director Oscar, and even casual moviegoers recognize his signature visual style, which is heavy on darkness and mood and gorgeous compositions.

Less associated with Fincher's name but equally deserving of attention are the consistently great performances he gets from his actors and the ferocious emotional impact of his movies.

"Seven," arguably the most influential film of the 1990s after "Pulp Fiction," was filled with grisly sights and unthinkable violations. But the biggest shock in the film — the one you remembered the most — happened off-screen and relied entirely on the connection audiences formed with the two detectives played by Brad Pitt and Morgan Freeman.

World-weary cops were already a cliche before "Seven," but the movie's protagonists feel unique and fully-realized regardless.

Similarly, the best thing about Fincher's take on "The Girl with the Dragon Tattoo" is not the central mystery, which is somewhat laborious, or the film's more extreme sequences, which include the infamous brutalization and rape of Lisbeth and the hair-raising revenge she takes on her attacker. Fincher's name has become synonymous with explicit violence and images, a result of the intensity of his movies.

But his adaptation of Larsson's novel is less explicit than the Swedish-language film.

"The book is infinitely more violent than what we could pack into 21/2; hours," Fincher says. "The rape and the degradation Lisbeth is subjected to in the novel is unbelievable. And we changed that — not to make it easier on the audience, but because it simply wasn't necessary for him to burn her and pierce her and do all those awful things.

"A big part of what I'm constantly deciding when I make a movie is 'How late can I come into this scene and still make my point? How much do I have to show before I can move on?' I am looking for the psychological underpinnings of stuff. I don't want to have to show you everything.

"The script was a monster, and we cut a lot of it. We cut a lot from the book and a lot from the script. I am looking for the psychological underpinnings of stuff. I don't want to have to show you everything.

"The first time we showed the rape scene to the studio, (Sony Pictures Entertainment co-chairman) Amy Pascal said, 'I know everything that's going on in this scene, and I didn't see any of it.' That to me is the highest compliment. That is what filmmaking is about — involving the audience to see things in their head."

This is not to suggest that "The Girl with the Dragon Tattoo" is fun for the whole family. The movie could be described as a romance spiked in blood, depravity and voracious evil. It pushes the limits of its R rating, the way Fincher's pictures often do.

But the movie is still — and this is important — a love story.

"I didn't need to make another movie about aberrant people doing horrible things to strangers," Fincher says. "The only reason I wanted to make this movie was the relationship between Lisbeth and Blomkvist. I thought it was extremely poignant. I felt that when I read the book, and I felt it in a different way when I saw Niels' movie. But I thought there was still room for further exploration. The friendship and love affair between this team of detectives was something I had no experience dealing with in movies. And Lisbeth still had lots of facets left for us to see."

Although the role required extensive nudity, several actresses lobbied hard to play Lisbeth, including Carey Mulligan and Scarlett Johansson. But Fincher, worried that a famous name would get in the way of the character, ultimately went with Mara, who made a deep impression after breaking up with Mark Zuckerberg (Jesse Eisenberg) in the amazing opening scene of "The Social Network."

Diehard "Dragon Tattoo" fans, who are legion, have been eyeing the Hollywood remake with understandable skepticism, arguing that another movie is redundant and crassly commercial. But Fincher's film makes up for what it lacks in surprise and freshness with a profound melancholy and the scorching chemistry between its two leads, an element the original didn't really have. The movie's box office prospects are bright, and Craig and Mara have already committed to starring in the adaptations of Larsson's two subsequent novels.

Fincher, who is circling a movie inspired by Jules Verne's "20,000 Leagues Under the Sea" as his next film, ends "The Girl with the Dragon Tattoo" with a scene that practically begs for a "To Be Continued" title card. But he says he is taking a wait-and-see approach to the rest of the Larsson trilogy.

"I'm hoping I get a call when the world decides it needs two sequels," Fincher says. "But it doesn't make sense to count your chickens before the audience decides they want more. And I'm not really in the head space to say what I'm going to be doing four years from now."