One year went by. Then two, three, four.

Finally, almost six years after they wrapped, Gillian Anderson found herself sitting in a room again with David Duchovny and "X-Files" creator Chris Carter.

"It was quite a monumental event," Anderson says of the first time they gathered to read through the script of the long-awaited second movie, "The X-Files: I Want to Believe." "On the one hand, it felt incredibly familiar and kind of melancholy and sweet and wistful in some way. And on the other hand it felt strange and awkward and like I was an impostor somehow on this other world."

It was the world Anderson inhabited for most of her young adult life. She landed the role of FBI Agent Dana Scully on the cult sci-fi series when she was just 24 and spent nearly a decade chasing aliens through the snowdrifts of Vancouver, where it was shot.

Last week, after flying to Los Angeles from London -- the city that's been her home for the past five years -- the 39-year old actress grabbed a bite to eat and happened upon "a table full of giggly 20-something girls drinking and talking nonstop."

"When I think to myself, 'Where was I then?' I forget that I ended up skipping a huge chunk of that period, because I was working," she says. "I was very myopic during the series . . . but I don't regret it in any way."

Agent Scully was a role that propelled her from anonymous to iconic and left a mark she never could have imaged at the outset.

Career-wise, too, Scully seemed fastened to Anderson after the series ended. She recalls fearing that she'd be offered only roles that were Scully-like, serious and probing. Instead, it was perhaps worse -- "people just had a hard time seeing where Scully would fit into their films," she says. "They couldn't make the leap to it being Gillian and not Scully and that I might be able to do other things."

Eventually some directors did take the risk, casting Anderson in several London stage productions, a BBC adaptation of "Bleak House" and the Oscar-winning feature film, "The Last King of Scotland." She also proceeded to take back the life ceded to "X-files" and Vancouver -- moving to London, having a second child, becoming pregnant with a third. (Anderson is due in October. It will be her second baby with boyfriend Mark Griffiths. She is twice divorced.)

Crawling back into the role of Scully could, Anderson knows, set her back a step in the process of professionally untying herself from the character. This time around, Scully and Mulder, Duchovny's character, are enlisted in the search for a missing FBI agent that hinges on an ex-priest's psychic visions. The chase tests their faith in God and the unseen, as well as their relationship with each other.

It has little of the alien-lore that propelled the television series, which, as it turns out, is fine with Anderson, who used to read the spooky scripts in the daytime, lest she lose sleep at night.

"I can't do scary," she admits. "My daughter watches the most horrific horror films. . . . I walk through the room to get something on the other side of the room, and if I even hear the music, I get nightmares. It's true. It's so pathetic."

Anderson, Duchovny and Carter agreed they wanted to do this movie even as the show was beginning to wrap. Even if the film does reinforce her perceived union with Scully, the trade off is worth it, she says.

"I wasn't gonna let this experience of this reunion pass by because that might be the case," the actress explains. And, she adds, "I don't think that will happen. I've done enough stuff already and . . . have things scheduled for the future that are different, so I don't think that will be an issue."

High on that list of upcoming projects is a biopic of Martha Gellhorn, a pioneering 20th-century journalist and third wife of Ernest Hemingway. .

The actress is also slated to appear as Nora in Ibsen's "A Doll's House," at the Donmar Warehouse in London next spring.

Last week began an online auction of hundreds of bits of "X-Files" paraphernalia Anderson had been keeping in storage for the past few years. Going through the boxes with an assistant was "kind of like Christmas," she said. Some of the artifacts "are quite intimate and special, so uncovering those and remembering that time was really cool."

There's been a lot of that -- remembering -- since the old team began shooting their new movie in December. But in the midst of it, it wasn't just remembering. It was something more like savoring.

"It was definitely a reunion for all of us. The odd thing is, as much as you build things up and as much as you get excited . . . it very quickly, within the first week, becomes a job," she said. "It just becomes about survival through the hours and the weather and all that stuff.

"And you have to keep pinching yourself and waking up and going, 'Hang on a second -- hang on to this! 'Cause this may be the last time.' "