(Sony Pictures)

When it comes to horror movies, there are few moments more iconic than this: Carrie White, standing up on the prom stage, wide-eyed and covered in blood.

Thirty-seven years later, it's the image movie fans associate most with the original Brian De Palma film, whether they've actually seen it or not. So as much as director Kimberly Peirce and her new Carrie, Chloe Moretz, want to chart their own course in the upcoming remake of the 1976 horror classic, they're also well-aware of the importance of getting moments like this just right.

That means finding their way back to the original source material (Stephen King's celebrated first novel) in order to update the chilling story for modern audiences, infusing it with new blood without losing any of its timeless impact.

In the 2013 version, Moretz stars in the role that Sissy Spacek first made famous, of a shy outcast pushed over the edge by both her deeply religious mother (now played by Julianne Moore) and high school classmates, unleashing her destructive telekinetic powers.

Moviefone visited the set of the "Carrie" remake in Toronto, where we talked to the cast and crew about making this version their own and how they handled the story's most iconic elements. Here's all you need to know about the new "Carrie."

The Filmmakers Want To Prove Skeptics Wrong
Whenever a new remake is announced, especially of a horror classic like "Carrie," online message boards light up, declaring sacrilege. But the filmmakers behind the 2013 update understand where those concerns are coming from. After all, they are attempting to remake a twice-Oscar-nominated movie.

Peirce, who's friends with De Palma, remembered her own initial hesitation about the project, saying, "When the idea first came up I thought, 'I love Brian. I love Brian's movie. I don't know why I would do that.' "

Moretz seconded that, saying that her first thoughts when she heard the studio would be remaking "Carrie" were, " 'Oh God, what does that entail? What type of remake is it gonna be? Is it gonna be a real beautiful movie, or something slasher-y and tentpole-y?' "

Even executive producer J. Miles Dale's daughter voiced her doubts. His 15-year-old, a huge fan of classic horror, "was worried when I told her we were remaking this movie," says Dale. "I love the first one, she loved the first one."

What ultimately changed their minds was the script, which aimed to be a more faithful adaptation of King's novel. "When I read the script I just inhaled it," says Moretz. "I couldn't imagine anyone else doing this role."

Peirce agreed, saying, "I fell so deeply in love with Carrie again that regardless of whether there had been another movie, even if it was a movie I loved and respected, this is a story I would make a movie of."

"Everybody says, 'Oh, another remake!' but Hollywood has remade movies for years. 'Scarface' was a remake. And now it's pretty well-revered, what De Palma did," points out producer Kevin Misher. "If you do it right for the generation that you're doing it for, it can also become a touchstone. We worked really hard to try and let this 'Carrie' speak to this generation."

So what about Dale's daughter? "Now she's happy," he says.

King Is Reserving Judgment, For Now
One more person the filmmakers would love to convince is Stephen King himself. After the prolific author expressed skepticism about early news of the remake (and then stumped for Lindsay Lohan as the new Carrie), the producers felt it was important to get in touch with him.

"We've communicated with Stephen King," says Misher. "I think the way in which he seems to operate with movies [based on his books] is that he wants to see the movie. That's a good pressure to have, I think. You've got to walk the walk and talk the talk and ultimately put the product up. And I think that we'll show him a good movie."

Then again, given King's oft-stated preference for the TV movie version of "The Shining" over Kubrick's, securing his blessing probably won't be make-or-break for the film.

They're Doing It By the Book
Something that ought to make King (and his fans) happy, however, is the filmmakers' stated preference to go back to the novel for the movie's blueprint, as opposed to De Palma's 1976 film, which took a few liberties.

Superficially, that means changing the name of Carrie's high school back to Ewen rather than Bates High, De Palma's "Psycho" reference, and Judy Greer's well-meaning teacher character back to Miss Desjardin. More importantly though, it also means upping the mayhem in the movie's final act, something the original wasn't able to do because of budget restrictions. "We're not quite blowing up a town, but there were more options available to us," says Misher.

"We get into the town destruction and the house destruction," promises Peirce. "There were certain reasons they couldn't do that back then, but because we can, it just means we can tell that full arc of the story."

For Peirce, that also means fleshing out the story's secondary characters, like Sue Snell (Gabriella Wilde) and Chris Hargensen (Portia Doubleday), who go from a one-note good girl versus bad girl dynamic to one that's more complicated, and satisfying.

When it comes to the infamous locker room scene, Sue is actually the catalyst in this version, according to Peirce: "She's the first person to do something in that locker room, and that sets off a chain reaction with the other girls." Teases Doubleday, "Sue isn't innocent, or she wouldn't really be my best friend."

"My character starts out as one of the mean girls," admits Wilde. But she appreciates the more rewarding arc Peirce has given her, saying, "Sue isn't so prevalent in the original movie as she is in the book and in this movie."

"Stephen King obviously created a good blueprint for all of the characters," says Ansel Elgort, who plays Tommy, Sue's boyfriend and Carrie's eventual prom date. "There's no one-sided character in this movie, or in the story."

It's no dig at De Palma, but Peirce explains that the book just inherently has "a more expanded canvas." And what she saw in it was the opportunity to really develop Chris as the film's villain, whose tormenting of Carrie eventually sets off all the death and destruction.

"Who is Chris? Why is she going to pick on this girl? How does that escalate? What I love about our Chris is that she's totally right that her life is getting effed-up because of Carrie White," says Peirce. "I made sure to make it that you really saw things through Chris' point of view."

There Will Be (A Lot Of) Blood
Remake or not, you can't make any version of "Carrie" without blood. And the 2013 update has that area covered, by the bucketful. Warren Appleby, the film's special effects coordinator, estimates, "We're, I think, upwards of 300, 400 gallons with all the testing that we've done." That's not for the entire movie, or even the climactic prom scene. That's just for the iconic blood drop onto Carrie's head. So yeah, expect some serious red stuff.

According to Peirce, most of that fake blood was spilled during weeks of fine-tuning the drop, where they meticulously varied both the amount and thickness of the blood, as well as the technique used to drop it. Eventually they settled on five gallons, and having the tin bucket move slightly so the cascade of blood splattered more uniformly.

All the fine-tuning is understandable, because when it comes to arguably the most important shot in the entire movie, everything needs to be perfect. Still, the last thing Appleby wanted to hear from reporters were any more backseat suggestions about the bucket rig or the blood.

Moretz was much more gung-ho about the process, and she'd already done the drop once before. "Literally 30 people just starting filing in trying to watch it. It was so cool," she says. Her only concern now was making sure the next attempt didn't knock her over, saying, "It's like five gallons of a liquid being dumped on your head so it's really heavy."

With only one shot that night at their leading lady, though, it was Moretz's stand-in who had to weather the final calibrations. With sheets of plastic covering the set dressing, an army of crewmembers holding towels at the ready, and a growing crowd of rubberneckers, the testing got underway. The first missed completely, the second didn't, hitting the stand-in's face, but not her dress. In a matter of seconds, the towels were offered, wet vacs fired up, and the entire enterprise reset for another go.

Eventually, with the bugs worked out, it was Moretz's turn. This time, it worked perfectly. The actress got a big round of applause and was whisked away for debriefing and clean-up. Reflecting on the scene afterwards, Dale was relieved they finally got the shot. "It's going to be great," he decides. "[After] another three days of coverage." Weep for the poor stand-in.

Yes, It's Going to Be R-Rated
If you couldn't tell, hundreds of gallons of blood means that the 2013 "Carrie" is going to be rated R, not PG-13, like some recent horror remakes that have had fans crying blasphemy. From the beginning, the studio was always committed to making their "Carrie" R-rated, which pleasantly surprised Misher. "Being an old studio hand, you're always sort of discussing the PG-13/R-rated line," he explains. But that conversation never happened here.

He credits that to their choice in director, saying, "Once you're bringing Kim Peirce on to do 'Carrie,' and what you're selling here is not the gore and the shock and the splatter, as much as you're selling the reality and the intensity and the suspense, I think then it naturally led you towards an R."

"The funny thing is, I can't tell that you that I know the difference between PG-13 and R," laughs Peirce. "I know the difference between R and X, 'cause I've gotten an X and I had to fight it down."

"The only difference that I've noticed is the nudity," offers Greer. "There's not as much nudity as the original, and nudity just means something so different now than it did in 1976. I'm finding now that more and more nudity is so rarely important to the story in any film."

Along those lines, Peirce's main concern was making sure the film was never exploitative, while keeping its central violence -- both physical and emotional -- authentic and real. According to the director, the goal is simple: "How deep can you go? How much can you show? How explicit can you be?"

Those are questions Peirce asks herself every day during filming. "You're always saying 'How much is too much?' I think you cross the line in order to come back from the line," she says. "As much as I can, I want it to be creepy and horrifying, but real horror in the Kubrick sense."

Misher agrees: "We were, from the beginning, aspiring to make a classic horror movie. Which has real characters, not just shock scares. There'll be shock scares in this, and some pretty tough stuff at times. But what's as important as the horror is also the evolving and inexorable suspense of it all."

The Story Is Being Taken Into 2013
Of course, updating King's story for modern audiences by moving it forward in time almost 40 years also means having to take into account modern technology, and how it affects and amplifies the bullying that finally sends Carrie over the edge.

"All we really did was try to lay in elements of Facebook and Internet bullying," explains Misher. "But it didn't become something that took over the story. We stayed very true to the Stephen King of it all, but in this day and age, somebody's going to text somebody else."

For Alex Russell, who plays Billy, Chris' boyfriend and co-conspirator, it's just a part of the modern high school experience. Of the wide array of social media available to teens, he says, "Sadly, they're other ways that if you're 14 you can torment people and make their life hell."

The speed at which kids can humiliate each other now, as well as the platforms they use to do so had to be included, according to Peirce. It even became a central plot point in the initial locker room scene. "Chris has her cell phone and she's filming when they're throwing the tampons. You needed that," Peirce explains. "And then she posts it [online], and there are pictures of it and there are images of it at the prom." You had to expect those giant screens next to the prom set stage would be used for more than just school-approved slideshows.

"I love that they incorporated that, because nowadays, everyone has their phones constantly," says Doubleday. "I think it just expands it and expands the pain of a situation like that, so that everyone can be in on something horrible and easily access it."

"I've seen the bathroom stuff and what I've seen of it has made me cry," agrees Greer. "It makes me feel sad to think of kids going through that. Just watching [Chloe's] performance in the shower scene is really heartbreaking."

For anyone still on the fence, consider this: despite repeated warnings that there would be no pictures or video allowed during the evening's blood drop tests, most of the young principal cast was still laughing and shooting away on their iPhones anyway. That's just the reality of our world these days. How could you not include it?

This Is Kimberly Peirce's Superhero Movie
Or as close as the "Boys Don't Cry" director will come to one. Because as far as she's concerned, "Carrie" is as much a superhero movie as it is a supernatural one.

"With the blood comes the powers," Peirce says, referring to Carrie's telekinesis. So she turned to comic book movies to help structure that storyline. "Really what I aimed for was to write more of an arc for those powers. So it is in some ways a superhero origin story, but her being the kind of superhero that Carrie is," she explains.

Says Peirce, "At first she doesn't understand that she has them. Then in the middle part, she has them more and more. She starts to look at them and think, 'Oh, maybe I can use these for good. Maybe I can have fun with them.' Then she starts to realize, 'Oh, these are things that could hurt people and I don't want to hurt people with them.' So she's trying to refuse using them, and in the end they leak out."

Visual effects supervisor Dennis Berardi talked about developing Carrie's telekinesis for the film, saying, "We've come up with a scale of what the force is. We did that early on where we went through the script and Kim said, 'This is a 1, this is a 2, this is a 3...' " So, what's a 10? You'll know it when you see it, says Berardi, "We've got some pretty great stuff planned there."

"I'll tell you what, it's pretty cool. We did some on-set visual effects, so in one of these scenes I'm practicing my TK and when I move my hand over something it actually moves. So it's a little bit like 'Harry Potter,' " Moretz laughs. "It's really cool. At one point in your life, you've looked a remote and been like 'Move!' But it actually happened."

It's A Mother/Daughter Story At Heart
For all the special effects and mayhem, at the center of the story, it's still about Carrie and Margaret White for Peirce and Moretz.

"That's the spine of the whole movie, the mother/daughter relationship," says Peirce. "The funny thing is that I've been wanting to do a mother/daughter movie for a long time and who knew it would be this?"

When it comes to Margaret, Misher says, "There's a very sweet relationship between her and her daughter at various times in this movie, that it actually breaks your heart that it's not going to end well."

"So you get that real teenager-mother relationship," Misher continues. And when it comes to Margaret's religious zeal, a major element in any version of the story, he explains that Moore wanted her to be more than just a stereotypical Bible-thumper. "Clearly, she's bastardized that into her own form of controlling her daughter," he says. All of which makes her a more classic villain in the producer's eyes.

"In our movie, Margaret locks Carrie in the closet, that's a staple of the story, right? We also have Carrie lock Margaret in the closet," says Peirce. "Oh wow, does Julianne go there. And it's wonderful."

They Make "Carrie" Their Own
Still, with Spacek and Piper Laurie earning Oscar nominations for their roles in the original film, Moretz and Moore knew it would be difficult to get out from behind their long shadows.

"When you read the script, you couldn't help but read the dialogue -- some of which is the same, some is different -- with Piper Laurie's voice," says Misher. But Moore brought an entirely different character to set. That's the benefit of casting a veteran actress, according to Misher: "She fully changed the character to embody it in the way that she wanted."

Moretz found it harder to distance herself from Spacek's performance, saying, "Everyone knows the typical hands-out, eyes-open look." Even for photoshoots, she'd be asked to replicate the iconic pose, but she always refused, saying, "The minute I do that, I'll be stealing someone else's character. My main thing about this film was building my own Carrie, and she's not what Sissy did, she's not what De Palma made Carrie to be, it's what Kim and I have constructed."

Ultimately, it comes down to establishing a connection with the audience. "The only way you can make it unique and not live in the shadow of something else is to make the audience care about the characters," says Misher. "I think working inside character is the only way we can differentiate this 'Carrie' from the old 'Carrie.' "

You're Going To Want To Stay Until The End
Fans of the original still remember De Palma's terrifying final scene, and while that sort of shock only works once, the filmmakers are looking to duplicate the spirit of that one last final scare for their updated version.

"I felt all along that you can't really top that moment," says Dale. "It was such a signature moment for the movie, you can't top it. So we've come up with a little twist on it that we think is going to work. But that was the one thing we said, you actually can't do that again. Because if you're expecting a scare like that, it's really not a scare."

Instead, they're giving it their own twist. "We're going to do something interesting that actually pays homage to the De Palma movie," Dale promises. "That's kind of the biggest homage in the movie in that scene, and then we're going to do something else just when everyone's on their heels."

So even though you may think you've already seen this story, the new "Carrie" just might have some surprises for you after all. Consider yourself warned.

"Carrie" opens on October 18, 2013.

Newest Trailer For 'Carrie' Just Released