After six years of silence, Mulder and Scully are about to battle another dark mystery -- this time on the big screen. What can you expect? Whitney Pastorek sums up her yearlong search for answers

Night is falling in British Columbia. The air is damp and cold, and the buzz of a helicopter is fading into the distance. I am attempting to collect information on the set of The X-Files: I Want to Believe, but instead, to avoid being caught on camera, I am lying facedown in a muddy field. Yeah, I think to myself. This seems about right.

Full disclosure: I am an X-Phile. I am also a shipper — short for ''relationshipper,'' online lingo for those who believe that the relationship between Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) should involve getting it on. Between 1993 and 2002, I logged unjustifiably long hours on the Internet discussing that and other aspects of Chris Carter's paranormal creation, and when the first X-Files movie grossed $84 million in 1998, at least $20 of it came from me. I begged a teaser poster off my local multiplex manager, sticking it in a plastic frame from Wal-Mart. The frame died years ago, but the poster — which reads, simply, FIGHT — still hangs on my office wall. There have been times, especially of late, when I've turned to it for inspiration.

The television series ended with Mulder and Scully driving toward an uncertain future. That uncertainty soon extended to the possibility of a second film, thanks to tired actors, the 10 million viewers who'd walked away by the show's final season, and a 2005 profit-participation lawsuit Carter brought against Fox Television. But once the suit was settled, Carter and producer Frank Spotnitz began writing, and on July 14, 2007, David Duchovny told a roomful of unsuspecting journalists he'd most likely see a script the following week.

A few days later, I interview Duchovny for a profile, and my year of X-Files begins. ''There's nothing you can tell me?'' I ask. ''Not and feel that I was telling the truth, no,'' he answers.

Shooting starts in December, with Carter in his feature-film directing debut. The world learns they're making a stand-alone, alien-free thriller, set in the present day and costarring Amanda Peet and Xzibit as FBI agents and Billy Connolly as a shady priest named Father Joe. But except for one grainy werewolf photo making fansite rounds, security for the project is governmentally tight, and everyone's playing along. When I visit the set in March, Duchovny fends me off with sarcasm (''No, the culture has shifted, and there's no room for The X-Files because Lost is on everybody's mind''), and Anderson is adorably bad at the secrecy game. ''I think she's made certain choices in her life, that follow, um, perfectly with who she is,'' she says of Scully's journey, before cutting herself off and whispering, ''I don't know how to talk about this!'' She also apologizes for eating carrots in front of me, but at least carrots can't be off the record.

Spotnitz gets the obfuscation gold star for at one point actually answering a question with, ''Well, the truth, the truth. It's out there. What is the truth?'' Luckily, he expands. ''I think the truth is in Mulder and Scully, these two opposites coming together,'' he says. ''This could be the last time we ever visit this world, and we wanted to say something fundamental about it.'' Then he makes me promise not to spoil their movie, and lets me see some action. Suddenly, there they are: Mulder and Scully having a tense discussion in a bathroom; running to board the aforementioned helicopter; saying goodbye in a scene I now know is the movie's denouement. Forbidden to write down anything substantive, I focus on snippets of dialogue — darkness, procedure, tranquilizer, severed arm. Meanwhile, I manage to totally overlook three innocuous little words that turn out to encompass the film's emotional core, as well as the filmmakers' struggle to get it made. I can't tell you what they are, of course, but I'm pretty sure they're what Spotnitz means when he says, ''Six years ago, it would have been a different movie. It's very much anchored in what matters to us right now. I'd even say it's personal.''

My trip to the set also includes one appropriately bizarre incident in the dead of night, after Carter suggests I drive him and his standard poodle, Larry, the hour or so back to their apartment. (Carter loves dogs, and cast both his veterinarians in the movie; this factoid is less random than it seems.) As we hurtle down a dark Canadian highway, I try to navigate and play hardball at the same time: Any fear that the audience for this franchise has moved on, and they're not coming back? ''I'm not making this movie out of fear,'' Carter replies, in his Zen-master way. ''I'm just trying to make the best movie I can.'' Assuming the fans do return in force, Carter says he's interested in a follow-up, possibly involving the apocalyptic theories swirling around the year 2012, when the endgame of the show's conspiracy was originally scheduled to take place. Then he excitedly directs me down a crackhead's dream of an alley that leads to his garage door, where someone — he doesn't know who — has spray-painted NO SOLUTION IS COMING 2012 in giant black letters. ''That's spooky,'' I say. ''It is spooky,'' he says, and as a suspicious-looking gentleman lurches toward us from a doorway, he guides me back to his better-lit front gate and bids me goodnight.

By June, the movie's trailer is online — lots of snow and eerie operating rooms — and I get asked to host a ''sneak peek'' of XF:IWTB at the L.A. Film Festival, alongside Carter, Spotnitz, and Duchovny. Despite sweltering temperatures on the streets of L.A., hundreds of people line up outside the theater hours in advance, and the predominantly female crowd spends the afternoon shrieking with glee. In the face of this deafening devotion, it's especially nice to hear Duchovny say he's filled with responsibility to meet fan expectations; in March, he'd refused to acknowledge any such obligation. ''I guess it's like a band that doesn't like to play its old songs,'' he later says of this change of heart. ''I realized that the old song is the Mulder-Scully relationship, and they want that. It's kind of beautiful.''

The fans also want this film to succeed; thus, the first question from the floor is, ''Why has there not been much TV promotion?'' Spotnitz — who's been getting plenty of e-mail on the same subject — assures them the studio has promised that by its July 25 opening, ''everyone will know about this movie.'' Fox reports it's got 95 percent awareness — in the face of The Dark Knight, no less. Still, the Philes are scheduling meet-ups, exhorting their friends to action, and planning to see it 10 times each. I lurk online to see what they know about the plot, and as I click through websites and message boards, it feels just like old times. Which is when I realize: Dammit, I'm a fan, and there's one resource I haven't yet tried.

Fox's official X-Files ''fan liaison'' is Gia Milinovich. She lives in England, and I knew she'd seen the script because she recorded herself paging through it, and put the video on YouTube. In her opinion, the new story is more ''in-depth'' than the TV show. ''It's scarier,'' she says. ''And it's more grown-up, I suppose.'' Asked to compare it to something in the X-canon, she picks ''Milagro,'' from season 6: a stand-alone, alien-free thriller that just happens to include some meaty Mulder-Scully relationship moments. Finally, she confirms that new spoilers leaking out of the fansites are not a hoax, and implores me not to look at them. They just contain shippery stuff, she says, no real plot points — and anyway, she thinks it's not the end of the world. ''The vast majority of people aren't even going to hear about it,'' she says of the leaks. ''But it's made the fans excited. They were getting really fed up with all the secrecy.''

On July 16, 2008, I am permitted by the paranoid powers that be to see the movie, and everything comes together at last — especially Carter's statement that, to him, science has become ''a religion of sorts.'' Just as the filmmakers insisted all along, the movie requires only basic knowledge of the television series to enjoy — Mulder's a believer, Scully's a skeptic, and together they fight spooky crime — but it's filled with cameos and references that will set the fans to shrieking. It is also strangely comforting, a welcome reminder of that time not so very long ago when the scariest thing in the world was the weird dude down the street who might be doing something very, very bad with his set of surgical tools. Given the film's reportedly bargain budget of $30 million — and the success of beloved-but-long-dormant franchises so far this summer — there's a good chance Carter could be making X-Files 3 right around 2012.

In the absence of aliens and conspiracies and brain-crushing mythology, The X-Files: I Want to Believe simply comes down to the joy of watching Mulder and Scully together again. We've been given one more chance to revel in the depth of these characters and their commitment to one another. Along with a lesson in patience, that's what Carter was going for all along. ''I want you to take that relationship and imagine it could be real,'' he says, and he admits something I've always secretly suspected: ''Maybe I'm the original shipper.''