Ten years after the ground-breaking 3D video game Doom was first unleashed, its latest sequel sees the franchise evolve into what its creators describe as an "interactive horror movie".
By James Bregman
BBC News Online staff
The original Doom was released in 1994 and offered fiendishly addictive gameplay.
Horrors lies in wait for gamers in Doom 3
The player took on the role of a soldier battling against monsters from Hell in a novel 3D-viewed science facility. Revolutionary at the time, it now looks primitive.
Doom 3, which goes on sale in Europe this week, is a sophisticated remake that approaches the original story with the full benefits of 2004 technology, enabling a fuller and freakier array of monsters.
"There are undead creatures and then demons," says Todd Hollenshead, CEO of the game's makers, id Software.
"We've got zombies, maggots, spidery demons, demonified undead marines, the Hellknight, the cherubs, lost souls with flying heads."
Several of these foes should be at least vaguely familiar to the first game's many fans.
"It's a retelling of the original," Mr Hollenshead told BBC News Online.
"We pretend that Doom and Doom 2 didn't happen. Those games were massively successful in their own right so we had this great creative universe to draw upon, but really only the surface of it had been scratched because of the technological limitations of the time."
Long time coming
It is not uncommon for major video games to be finished much later than planned, but Doom 3 is arriving more than a year after it was first expected, something the developers put down to the cutting-edge technology involved.
"The biggest challenge you face is figuring out how to leverage new technology that you've never worked with before," says Mr Hollenshead.
"There were no examples for us to learn by when we began creating content for Doom 3. There wasn't any game-path to follow so we were creating our own path."
He says the game's revolutionary use of "bump-mapping" techniques, which add complexity to rendered surfaces of 3D objects, mean the creature models are as detailed as characters in computer-generated feature films like Shrek.
But making a game scary requires a lot more than simply ensuring the graphics are realistic.
"The game set out to be an interactive horror film and we knew we could do it from a visual standpoint.
"But the question was, can you bring that non-interactive experience to an interactive video game experience? And that's the big challenge.
"There are a number of elements that lend themselves to the fear factor, one of which is just the atmosphere itself. The demons are scary, they have big evil teeth. They're visually appalling.
"We don't have music per se, but there are ambient sounds, which lead to a very overwhelming feeling of tension. Then there are the things that jump out at you.
"So it has to do with pacing. You get people in the mode where they're uneasy, then they think something's coming up and it's not what they've expected, and then they've let their guard down."
Mr Hollenshead adds that inspiration was drawn from a number of feature films like Aliens that managed to ramp up the fear factor.
"We really looked hard at the film business at how directors and set designers use lighting to set mood and that is a lot of what goes on in Doom 3 - one of the best uses of light is to make the atmosphere very scary."
Whilst the lighting and effects are certainly impressive, getting their full effect requires a fairly powerful computer.
The game needs a powerful computer to be at is best
But Mr Hollenshead is thoroughly unrepentant about the game's demanding hardware requirements.
"I know our games are famous, or notorious depending on your point of view, for encouraging people to upgrade their hardware," he says.
"Doom 3's minimum specification system was probably a beefy system a couple of years ago, so going back a couple of years in the market is far enough for us."
A big-screen version of Doom has long been mooted, and may finally be on the verge of seeing light of day, with Universal Pictures setting up the production in Prague.
Mr Hollenshead says he is happy with the working script and hopes a finished film will arrive in cinemas within the next year and a half.
He points to the first Tomb Raider and Mortal Kombat film adaptations to show that games can transfer into decent action movies.
"Alright, there have been some stinkers, but a lot of that happens when the movie is just relying so much on the game to sell tickets that they don't think the movie has to be good in its own right."
The game developers are continuing to work closely with the film-makers to ensure the game's immense reputation will not be tarnished.
"We went in to it with the attitude that we make video games not movies, so we won't tell you guys how to do your business but we expect what we do to be good," he says.
Doom 3 is now available on PC. An Xbox version is due to go on sale in September