LOS ANGELES (AP) — Chris Carter, creator of The X-Files and TV’s reigning horror merchant, has the rapt attention of his writing staff as he describes a vivid little scene.

A man sits in front of his TV set. In the attic above him, a rotting corpse silently begins to shed the vermin that infest it.

“They crawl down into the ceiling … and it’s drip, drip,” Carter intones. “The maggots are dripping into my den.”

This, it turns out, is no X-Files plot; it’s Carter’s own tale of a dead rat in his house.

Yuck, says a visitor. Oooo, murmur the writers, continuing to nibble happily on frozen yogurt treats.

This is what passes for light banter during a script session for FOX TV’s sleekly morbid drama, shown on Global in Canada, about a pair of FBI agents, Fox Mulder and Dana Scully, who probe UFOs, government conspiracies and freakish crimes.

Obviously, being in the right frame of mind helps to craft the dark and clever stories that have turned many Friday night TV viewers into X-Files junkies and made stars of lead actors David Duchovny and Gillian Anderson.

Attention to detail also helps.

In a homey-looking bungalow on the 20th Century-Fox lot in West Los Angeles, Carter and staff conduct a painstaking appraisal of each episode as it progresses from concept to finished script.

The focus of the meeting is a one-metre by 1.5-metre bulletin board covered with a couple of dozen index cards noting, succinctly, the plot points of each of an episode’s four acts — as separated by commercial breaks — and the opening “teaser” scene.

The person with the task of delivering a completed script talks through the story, using the cards as reference points. In this session, writer Jon Shiban is telling the tale of a vengeful army veteran turned killer.

Every twist and turn is up for debate, including the injuries that make the character an improbable murder suspect. Shiban has described him as a quadriplegic who uses an out-of-body trick, astral projection, to kill.

It’s not quite enough for Carter.

“I think you should go all the way,” the creator-producer says. He wants to see the character turned into a quadruple amputee, a more helpless and haunting figure.

That’s the startling sensibility Carter brings to the series. He turns out a fair number of scripts himself, especially those dealing with the drama’s pivot point, the obsessive quest by Mulder (Duchovny) to prove aliens are here.

Episodes written by others still bear his stamp. The soft-spoken Carter is a protective if low-key parent of the series filmed in Vancouver.

One plot twist in the astral projection drama, an abortive suicide, draws an approving nod from Carter. “That’s a cool scene,” he says, betraying his roots as a native Californian who spent five years editing Surfing magazine.

“There’s no creepy boo scene here,” he comments at another point.

(His droll sense of humor pervades the series: “Would you say your hair is normal or dry?” a serial killer asks captive Scully in one episode as he prepares a bizarre ritual bath.)

After Carter and the group weigh in on a story, the main writer heads for the seclusion of office or home to create the finished 43-minute, 11-second script.

That, says staff writer Darin Morgan, is when the pressure kicks in.

“You have so many production people up in Vancouver waiting for your script so they can begin work. If you’re late, you’re causing enormous production problems. You’ve got $1 million riding on you,” he says, the approximate price tag for each X-Files hour.

Locations must be scouted, costumes created and the limits of special effects — for a show rich with masterful monsters and convincing spaceships — explored.

“You have to know what you can do,” Morgan says. “You can’t just write, ‘There’s a huge explosion.’ If there’s going to be a big effect like that, they (the production crew) need to know in advance.”

Meantime, other scripts in various stages of preparation are moving down the line. The show’s motto is “The truth is out there,” but the real goal is trying to stretch the limits of frightful fun.

Carter sees no end to the extreme possibilities. “I have faith there are hundreds of good X-Files episodes out there,” he says.

“I just want nothing more than to scare the pants off people for 24 episodes this year. That’s all I set out to do anyway. … It’s a ride. And the steeper the roller-coaster, the better.”