Prometheus, Ridley Scott's spiritual precursor to sci-fi shocker Alien, comes a cool 33 years after Ellen Ripley first faced off against a hideous monster in deep space.

Fans of the original movie and its sequels have dozens of questions about how the Prometheus plot ties into the Alien universe. But here's the gnarliest one: Is there anything as shocking as the original "chestburster" scene from three decades ago?

In short, yes. Wired recently caught up with Scott, Prometheus actress Noomi Rapace and writer Damon Lindelof about a horrifying scene from the R-rated movie, a nasty sequence that's sure to get viewers squirming when the film opens Friday in the United States.

(Spoiler alert: Major revelations follow.)

The classic combo of horror and science fiction changed forever when an H.R. Giger-designed xenomorph popped out of actor John Hurt's chest in Alien.

"For it to burst out of his chest was a gob-smacking experience," Scott told Wired. "My thought always was that he's going to split sinew, bone and separate his ribcage into a birth." The director points out that moments like this – surprising turning points within a screenplay – are the ultimate engines for storylines. "Once you get moving on a screenplay like that, you don't want to change it," he says.

Anyone who has watched a Prometheus trailer or TV spot can hear Rapace – the original Girl With the Dragon Tattoo, now playing heroine scientist Elizabeth Shaw – scream, "Get it out of me!" In a movie constructed of Alien DNA, that sentence can only mean trouble.

In this case, she finds out she's carrying something in her body on the moon LV-223 that leads her to the Med Pod – an automated medical device composed of an airtight operating shield with robotic surgical arms and a laser scalpel. Within moments of discovering that her body is carrying what can only be deemed as unwanted, she strips down and performs a self-induced alien-ectomy in the machine.

"In Jon Spaihts' [Prometheus] draft, it was a chestburster," said writer Damon Lindelof, who was brought on to spin the new movie into its own universe. "It is going to be scary, it is going to be visceral, and it is going to play into every woman's fear of something wrong with the baby inside."

Upon first reading about the painful procedure outlined in the script, Rapace said she had concerns about making the scene believable because it's so terrifyingly bizarre. "I spoke to Ridley about it and said that I would love to find a way to do it as real as possible – to not do it in CGI or to not cut up the scene into small pieces," the actress said. "We worked for four days on the scene and it messed me up completely."

The Med Pod – which looks like a claustrophobic cross between an MRI machine and a see-through casket – yields a horrifying spectacle that will surely stick with filmgoers, just as it haunted Rapace after filming.

"I had two dreams that I remember today," she said about the scene. "I woke up and I went into the loo, saw myself in the mirror, and I realized I had some kind of black veins that began to spread over my whole body. I started to wash my hands and thought the water was going to stop it somehow."

>"I was so terrified that I was crying, and I woke up and I was crying for real." — Noomi Rapace

Her second dream involved her touching her belly while a creature was moving around inside. "I was so terrified that I was crying, and I woke up and I was crying for real," the Swedish actress said.

Despite the grotesqueness of ripping a living creature from her womb with a laser, followed by the mechanical insertion of a row of gleaming staples across her bare abdomen, Rapace said she didn't feel exploited by filming the scene. "I never felt exposed like, 'I'm this girl, half-naked in front of the crew, screaming and crying and going through this very disturbed situation,'" she said. "It really felt like the two of us inside of it," she said of her and Scott.

The director's oeuvre is somewhat of a dichotomy in this way: He built his rep on movies that pair big ideas with short bursts of the gripping and the gross. Horrified viewers watched the titular cannibal in Hannibal serve Ray Liotta his own brain as the killer psychoanalyzes Agent Clarice Starling. Likewise, American Gangster had Denzel Washington putting a bullet in the head of a rival gang member in broad daylight, only to casually return to dinner with his family.

"I'm a sick fuck," Scott joked.

Marrying the two things is a particular skill the director possesses, and Prometheus is about much more than Rapace getting a grisly, graphic C-section.

"I think the scene kind of captures the whole question about creating life and what if the child and the thing that you created starts to turn against you," Rapace said. "We have those snakes in Sweden – black-and-yellow snakes – and they give birth to their babies up in trees. The babies fall down and the babies are poisonous. They'll bite and kill the mother if she's close to them. I think this scene embraces the whole problematic and disturbed relationship between parents and children. It's creating life, but with some kind of savage beauty."

Lindelof agreed. "In the same way that the first movie is terrifying, it ultimately boils down to a Michael Myers- or Jason Voorhees-like scenario, where it's just picking people off one at a time in chilling ways," he said. For Prometheus, it was his mandate to expose audiences to bold ideas rather than simply serving up a series of untimely deaths. But that doesn't mean he couldn't include what will probably be the most important horror sequence of the year.