In the five years since they last struggled with the supernatural in the X Files, the careers of David Duchovny and Gillian Anderson have diverged: he has struggled to find good projects, she has been acclaimed. Now they are to be reunited in the roles that made them.

When Chris Carter, the originator of the The X Files, first sat down with executives from 20th Century Fox to propose his idea for what was to become one of the greatest cult shows in modern television, Bill Clinton was a fresh face in the White House and promising to make the world a better place. But Carter told the suits from Fox that what he had in mind was not to put the smile back on the faces of Americans but rather to frighten them out of their wits. "There's nothing scary on network television any more. Let's do a scary show," he told them. And so began a process by which The X Files combined themes such as conspiracy theory, government cover-up, biological terror and decapitation to captivate a global following for almost a decade.  

The stars of the show, FBI Agents Dana Scully (played by Gillian Anderson) and Fox Mulder (David Duchovny), became Hollywood stars and the series spawned its own feature film, but it seemed that The X Files phenomenon had finally been undone when real-life events left television audiences feeling that they had been scared quite enough already, thank you. Writers working on the ninth and final season of the show in 2002, admitted that they were finding it difficult to compile scripts, compatible with the show's traditional themes, that audiences were able to stomach in the wake of the World Trade Centre attacks in September 2001.  

Yet, as one should perhaps expect of a programme that dabbled so much in the realms of science fiction, The X Files (catchlines: "The Truth is Out There" and "Trust No One"), is about to come back to life. Following a succession of false alarms, in which Carter, Anderson and Duchovny have expressed their desire for returning Mulder and Scully back into the line of duty, it seems a second movie is really going to happen after all. 

Duchovny, 46, spoke to a small group of journalists of the American Television Critics Association at the weekend and confided that work on the film is due to start in November. "Gillian is on board and I'm on board. It's November for a summer release," he said. "I've been talking to Chris and he's been giving me some progress reports. He actually called yesterday and said: 'Next week you should have something to read'."  

In spite of these comments, the legions of fans of the show, collectively known as X-Philes, could be excused for treating them with the sort of scepticism normally attributed to Agent Scully, due to the fact that Duchovny has been chomping at the bit to get back in front of the cameras for more than three years and has repeatedly made that known, only for the plans to be scuppered, largely due to a lawsuit which Carter slapped on Fox in 2005 following a dispute over the allocation of profits from the show.  

Duchovny has struggled to find work to match the thrill of playing Agent Mulder. He played a hand model in the film Zoolander in 2001, directed a film called House D in 2005, which received poor reviews, and last year took some unglamorous if well-paid work doing Pedigree Petfood commercials.  

But now The X Files legal wrangles have now been resolved and speaking to The Independent last night from a film festival in Italy, Anderson confirmed that she was set to begin filming sometime between October and January. "The script is imminent and we are meant to start doing it by the end of next year and beginning of this year," she said. "I have been for it from the beginning and I have been positive about it from the beginning."  

The Chicago-born actress, who spent her childhood in Crouch End, north London, and still speaks with an English accent, won an Emmy and a Golden Globe for her performances as Agent Scully and has gone on to further success in film and television since The X Files went off the air. She won a Bafta for her performance as Lady Dedlock in the BBC's adaptation of Bleak House and has recently appeared in a succession of British films, A Cock and Bull Story, The Last King of Scotland and Straightheads. She is currently working on the film version of British journalist Toby Young's book How to Lose Friends and Alienate People, which is being shot in London.  

Two more films, one called The Smell of Apples, which is due to be made in South Africa and a German co-production called Helen are also in the offing, although her availability might be compromised by the new X Files project. 

None the less, she said, the chance to play Scully again is irresistible. "It was not something I longed for on a regular basis but as soon as we start talking about doing it again I get very excited. There's always a bit of melancholy about it because of the amazing memories of the experience. It was a very intense period in all our lives and the thought that we are all going to come together again to do it - and possibly in Vancouver where it all started - is very exciting. A lot has happened in the past few years but we are excited by each other's company and I think it will be loads of fun actually."

Carter, 50, was originally advised that Anderson was not the right shape for the part of Scully but was determined that she was by far the best candidate. He set up Ten Thirteen Productions, named after his birthday, to make the show, which he dreamt up after having become bored of working on comedy programmes.  

He has made several other shows for Fox, including Millennium and Harsh Realm, both for Fox, but none of them have enjoyed anything like the same degree of success of The X Files, which ran for 201 episodes. The Lone Gunmen, a spin off from The X Files, began in 2001 and was well-received but was taken off the screen after only 13 episodes because of poor ratings.

Anderson, 37, said Carter had been working hard to make the follow-up feature film happen. "I think there were a lot of issues that have stopped it in the past but now it seems clear and they've got the contract details worked out and I guess Chris has had time to write it and all those things equal something positive," she said.

But the chances of a 10th series of the television show are precisely zero, she said. "It's just never going to happen, it's just not on the cards at all. I don't think we have the energy for it either of us." 

So the X-Philes, and indeed a potential younger audience of converts to the adventures of Mulder and Scully, will have to settle for another movie. In the years since they have been away there has been more than enough threat of global terror, government skullduggery, conspiracy theories and fears of evil- minded scientists and dark forces at play to provide an appetite for their return.  

"That's true and there's an opening for that," acknowledges Anderson before squashing any notion that the film will attempt to focus on such topical issues. "Except that I understand that the script is nothing to do with what some of the themes have been about in the past. It's going to be a very scary film about two characters who happen to be called Mulder and Scully. I don't think they are going to draw on any of the mythology or the conspiracy stuff, as far as I know. My understanding is that it's scary like a monster film."

Some of us might think the world is a frightening enough place already but evidently The X Files team thinks the time is right to scare us a great deal more.