High school can be a rough time for any kid: the peer pressure, the bullying, the hormones and even, on rare occasions, the studying. Sometimes, even for the best of us, the pressures of high school can become overwhelming. But when we visited the set the new DreamWorks action blockbuster 'I Am Number Four,' we learned that there's at least one thing worse than being in high school: being in a high school overrun by murderous alien beasts.

And you thought zits were a big problem.

Based on the young adult novel of the same name by authors Jobie Hughes and James Frey (yes, that James Frey), 'I Am Number Four' has been touted as the heir apparent to 'Harry Potter' and 'Twilight' since before the book was even published. Yet, as insanely popular as both of those series are, neither of them became true mega-hits until the movie adaptations introduced millions of new fans to the books.

So, will 'I Am Number Four' follow in their footsteps to become the latest fan obsession? That question will only be answered when the movie finally hits theaters on February 18, 2011. But after spending an afternoon talking with the folks bringing Number Four (played by up-and-comer Alex Pettyfer) and his friends to life, we did manage to learn the answers to a few other burning questions. Here, then, are nine things we learned from our visit to the 'I Am Number Four' set:

1. Their biggest casting problem was ... 'The A-Team'?
Early in the casting process, the producers of 'I Am Number Four' came very close to signing 'District 9' star Sharlto Copley to the key role of Number Four's fatherly mentor Henri. When that deal fell through and they instead turned to noted character actor Timothy Olyphant ('Deadwood,' 'Live Free or Die Hard') for the part, the Internet lit up with rumors that Sharlto had dropped out because they wouldn't let him wear enough alien prostheses in the movie.

But the true culprit behind Copley's departure? 'The A-Team.'

"'A-Team' was such a big movie for Fox," director D.J. Caruso ('Disturbia,' 'Eagle Eye') explained, "that when we were still starting to make the deal with Sharlto, we couldn't have him for this week and we couldn't have him for that week. And so we were trying to make a schedule work [but] ultimately we just kind of threw up our hands and said, 'We just can't accommodate this any more because we don't know what's going to happen.' Fox was being sort of really difficult about his dates. So we just finally decided just to back off.

"But it wasn't about, like, prosthetic noses or ears or something," said Caruso. "I don't know what that was about."

2. 'I Am Number Four' shares a secret connection with 'Transformers 3.'
'A-Team' wasn't the only big ticket action film to interfere with the production of 'I Am Number Four,' as 'Transformers 3' also forced the departure of a key member of the team: director Michael Bay.

"[Dreamworks] bought this for Michael Bay and I didn't think anything of it," Caruso told us. "It sounded like a cool idea. And then I think that Michael Bay started getting into 'Transformers 3' and so they called me and I read the manuscript. And I read one of the early drafts and then worked on that for a while and got involved, got the draft into good shape, slowly got it developed and then showed Bay the script after a couple of months. He liked it and I think that kind of jump-started it, but I think 'Transformers 3' kind of occupied Bay and took him in another direction. So they called me."





3. Changes to the screenplay led to changes in the books.
Fans of the book may be surprised when they see the finished film. Why? Because while the cast and crew strived to stay true to the spirit of the original text, a number of details were changed along the way.

"In the book, [Number Four] knows from page one what he's supposed to do," Caruso told us. "In the movie it takes him quite a while to kind of figure out who he is and what he wants to become. And I think that was what was dramatically and cinematically interesting to me -- who he thinks he is and who he really is are two completely different people. And he has to come to terms with understanding that who he wants to be isn't who he's going to become."

The good news is that if there's a sequel, it's likely to stay much closer to the source material for one simple reason: After reading the script for this movie, the authors will be changing the second book to match.

"It's interesting because [the authors] have just outlined the second book, so some of the stuff that we had in the movie kind of sparked different ideas," Caruso said. "I noticed that their outline for book two had changed a little bit. Which was kind of cool."

4. Kevin Durand's Mogadarian Commander steals the show -- even though he's not in the book.
Kevin Durand is known for playing some of the jerkiest villains on television and in cinema (see: Martin Keamy on 'Lost,' the Archangel Gabriel in 'Legion'). So it's no surprise that his evil Mogadarian Commander steals the show. Just don't look for the character in the book -- because he's not there.

"One of [executive producer Steven Spielberg]'s bigger notes that we kind of kept working on in the screenplay was to really try and give the Mog Commander a personality. And so we wrote a few things just as a trial basis and sort of ran it by Kevin and he sent us a tape and read it and it just sort of made sense. So we started to tailor stuff for him because he's just so great.

"We definitely sort of gave the Mogadorian Commander a dynamic sort of interesting presence. I wanted him to sort of be what Chris Walken was back in the late '80s, early '90s, in those movies where he [has] the rhythms and the odd dynamics of someone that you really don't know how comfortable to get around him. Kevin's done a good job."

5. Dianna Agron is nothing like her 'Glee' character. Really!
Dianna Agron may be best known for playing black-hearted cheerleader Quinn on 'Glee,' but don't bother telling that to her 'I Am Number Four' castmates -- they may not believe you. "She's such a beautiful human being" is about the worst thing we heard about Agron from leading man Alex Pettyfer, while Caruso took it a step farther by declaring that "she represents everything that's good about America."

But while Agron has become known as the go-to girl for every cheerleading role in Hollywood (her ex-cheerleader Sarah in 'I Am Number Four' follows not just 'Glee' but also a turn as a cheerleader in 'Heroes'), her dream gig wouldn't involve either singing or cheering, but something more serious. "As much as I love musicals, I think I would want to do something just really gritty," she told us. "A drama -- you know, just something completely different."

Dark and gritty? Now that's something Quinn could get behind, after all.





6. The cast and crew love to pack heat.
When we visited the film's Pittsburgh set, it turned out to be a little more dangerous than we expected -- and not just because they were filming a sequence in which a Mogadarian monstrosity smashes through the high school cafeteria window. No, it's because the cast was enamored with all the cool weapons the prop department had whipped up to fight back with.

"I get to carry for about half the film this giant alien shotgun, this 20-gauge," gushed Callan McAuliffe, who plays Number Four's best friend Sam. "That's pretty awesome. It lights up. It has these red lights on it and you can actually cock it. It's got a real 20-gauge shotgun inside it and, yeah, that's awesome."

On the other hand, Teresa Palmer, who plays fellow alien refugee Number Six, prefers knives to guns, explaining, "I have an incredible dagger with an electric blue light that looks pretty menacing. I carry that around throughout the film and stab a lot of evil aliens with it."

But while Caruso agrees that Number Six's dagger is "pretty amazing," he has a soft spot for the heavy ordnance the bad guys bring to the table. "The commander has a blaster that's phenomenal, he's blasting it towards the end of the movie. And it's just this huge gun and Kevin Durand just fires it. I love the commander's blaster."

7. The movie's real star? The iPad.
You'd think that Number Four's home planet, Lorien, would be chock full of amazing technology, but the most cutting edge device in the film is from right here on Earth: the iPad. During our set visit you couldn't take a step without tripping over one of the ubiquitous Apple devices, but they weren't just a trendy gimmick -- they were integral to how the film was being made.

"I realized about a week into the prep that my storyboards were on it, my pre-visuals were on it, my script was on it," Caruso explained. "And I really started getting emails from two of my storyboard artists working in Los Angeles. I have this application where I can mark up the boards and send them back. And so it just became this amazing production tool. And slowly but surely, eveyone's starting to get an iPad. And then I noticed the actors, they all got theirs...

"It's just become part of our cinematic culture. It really is an amazing cinematic tool. And it's amazing. I never thought I'd say that. I thought I would be cool and get one -- and now I don't even carry my script any more, I just carry my iPad."

8. Most of the cast has never read the book.
Squeamish book lovers should avert their eyes now, because it's true: most of the cast and crew has never even read the book that the film is based on. But it's not because they aren't interested in being faithful to the source. It's actually for a much simpler reason: The authors actually hadn't completed the book before filming began.

"I haven't read the book," Pettyfer told us. "Not because I'm a bad person, but because the book hadn't been finished until we started the film. And I had an idea from the script who Number Four was and I didn't want to have my mind taken somewhere else while I was filming. I definitely am 100% going to read it the day I finish. But I don't want any influence from anywhere else. I sat down with both writers and got the idea what the gist of what the character was and then kind of went off and put it into my own hands to see what I could do with it."

At least one cast member has sneaked a few peeks at the book, though -- but only the parts she's in. "I skipped forward," Palmer admitted. "I wanted to see where [Number Six] came in and what her entrance was like. It's funny because it's actually a little bit different to what we're doing in the film, so it's cool to pick out all of the little differences."

9. And in the sequel you can expect to see...

The cast may not have read the book, but that doesn't mean they're in the dark. In fact, thanks to conversation with the authors, the members of the cast already know what happens to their characters not just in the sequel but in some cases through all six planned volumes. Try as we might, we couldn't get any of them to spill the beans. But we did learn some secrets from an unlikely source: the director himself.

Unfortunately, we can't really tell you what Caruso told us without spoiling everything (sorry!) but he did allow us at least one tidbit: Fans can definitely expect to meet at least one more of the seven surviving Lorien teenagers.

But what strange activity is the mysterious Number Five up to? That's something you'll just have to wait for the sequel to find out.