Set visits are always an overwhelming experience – good looking people, stunning costumes, elaborate props, odd and often exotic locations, and controlled explosions. You name it, I've seen it. But never has a set visit actually left me suffering from twitchy post traumatic stress. You see, I had just come back from ComicCon when Cinematical sent me to the set of Paul. I had just finished unpacking and fumigating my clothes of con smell. I was still sorting through swag. All I knew was that filming was taking place in Albuquerque, and we'd be talking to Simon Pegg, Nick Frost, and director Greg Mottola. We were also required to ask ourselves just who, or what, is Paul ....

But once in Albuquerque, we were briefed. The setting would be San Diego ComicCon, and we were going to play the part of ComicCon Attendees. When seeking to cast these parts, they had gone to the usual suspects – DeNiro, Pacino, Day-Lewis – but their Method acting proved to be too shallow. They needed real geeks who had spent years immersing themselves in con, lining up for panels, cheering footage, and who had their own nerdy t-shirts to wear on set. (Guess who had packed "normal" shirts because she wears nerdy shirts the other 364 days of the year? Yours truly. They kept me anyway.) After a sleepless night and a trip to Starbucks, we trooped across the street to the Albuquerque Convention Center. We felt like dry mouthed zombies, so we were already in the con spirit. Day-Lewis, eat your heart out.
To be honest, I wasn't expecting much more than a generic convention set. Whenever any film or television show thrusts their hapless characters onto a convention floor, it's always pretty low rent – folding chairs, someone dressed as Chewbacca, "booths" of painful Marvel and DC knockoffs to skip the licensing fees, and all the attendees sport Coke-bottle glasses and Spock ears. It's Hollywood's idea of a convention, and it makes you cringe. Oh my God, this is what my friends and family think I do in my spare time.

But not the set of Paul. After all, Pegg and Frost are geeks. These are the man-boys of Spaced. They've done ComicCon several times. And if they're going to set a movie at ComicCon, nothing less than perfect authenticity will do. We were issued replica con badges (yes, with the familiar eyeball logo!) and given a once over for make-up and costume. Surrounding us were extras dressed as everything you've ever seen at SDCC. There were herds of slave Leias, Jedi, Wolverines, Klingons, Link, Zelda, stormtroopers, elves and hobbits, Star Trek uniforms, Ghostbusters -- you name it, it was there. The extras were stopping one another and taking photos of their costumes – "Whoa, gosh! Robocop! Too cool! Dude, can I get your photo?" -- as if they were already on the convention floor.

The similarities to con were already getting weird. Things got weirder when we were taken to a psuedo Hall H set, where we would be playing panel attendees. We were assigned seats based on our level of physical geekiness. I was initially sitting in the front row before it was loudly announced that I was "too pretty" and that they needed someone nerdier. Humbled, I crept back a few rows to sit behind Pegg and Frost. For the first and only time in my life, I now know what Megan Fox must feel like.

Surrounding us were a mixture of local extras and comic book luminaries. The guy next to me – possibly also too pretty to be a geek – turned out to be Image Comics' Joe Keatinge. He pointed out Andy Kuhn, who was sitting somewhere behind me, and The Walking Dead's Robert Kirkman. They all looked vaguely shell shocked. It may have been because it was 8am, but it's more likely because Image Comics had donated their booth to the Paul set. A mere week or two after breaking it down in San Diego, they'd had to rebuild it on Albuquerque's convention floor and "man" it again. The look on their faces said too soon.

Simon Pegg and Nick Frost arrived, and the local extras perked up and began whispering excitedly. It was time for action. Over and over again, we jumped up and screamed "as if the greatest geek thing you've ever seen in your lives is up there." Even watching Frost and Pegg from behind was funny, as they leapt up and waved their arms in excitement, and it was hard to keep cheering and not start laughing. After every take, they revved us up more. (The final take was proclaimed to be "as if Starbuck and Apollo were literally f***ing onstage!") We then had to enact a Q&A session. This time, the camera focused on my side of the hall and I tried really hard not to look directly into it. I tried my best to mimic the open-jawed horror I've felt at a number of Q&As. I know I'm overacting; I fully expect to land on the cutting room floor. Perhaps they'll CG someone more nerdy and talented right over me.

From "Hall H", we were taken to the convention room floor, where we online journalists experienced the shiver that may only be felt by war correspondents. We're right back in ComicCon. The aisle signs, the banners, the registration stalls, the food vendors, the booths – Zenescope, Sideshow Collectibles, Oni, Image, Top Cow were all there, being manned by the actual employees -- the carpet, the lifesize Jabba the Hutt, the herds of glassy-eyed attendees clutching swag bags ... it was all there. We all felt a mixture of admiration and nervous fear. "Oh. Oh geez. I feel like I never left. I'm having flashbacks. This is just weird."

We met producer Robert Graf on the floor, who revealed he had hoped to actually shoot at SDCC before he had been tipped off that the massive crowds made it impossible. Recreating it was the only solution. Using a generic con was unthinkable. It had to be the real SDCC, and Pegg, Frost, and Mottola were determined to do it as faithfully as possible. Production designer Jefferson Sage spent months combing through con photos for iconic pieces and tracking down vendors to try and recreate the convention. "It was rather a daunting prospect to think that we would make it look like Comic-Con. I mean, Comic-Con is vast and huge and how were we going to cheat it? ... [Using real booths] obviously gets us a much better approximation of a real Comic-Con than if we were trying to create it or fake it up." Even movie producers balk at the idea of trying to recreate one of the biggest fan events of the year. "If you try and make something like this and you make it generic, people see through that ... In a lot of movies, it's always easy to see when you create a fake corporation, it sticks out," says producer Robert Graf. "[But] choosing to do the real thing just introduces the added problem of trying to make it believable to people who are really fans and devotees and go year after year after year. It's a tough sell. I feel like they've done an admirable job. It's a good, close facsimile."

I can vouch for it. The only flaw was it was too clean. If you've been to SDCC, you know the floor is stained with pizza and Mountain Dew by Friday afternoon. But that's a health hazard no Hollywood production is going to risk. The rest of our day was spent watching Pegg and Frost zip around their model con, mouths agape, clutching authentic schedules. According to the call sheet, this isn't just their first day at SDCC, it's their first real glimpse of America. Their America. They're drunk on it. They're unaware their lives are about to change with their next stop – Area 51.

So, they recreated ComicCon. Sure, that speaks well of the care that's going into all aspects of production, but what is it all about? What the heck is Paul? Well, he's "a space traveling smart ass" (voiced by Seth Rogen) who has been living in Area 51 for the past 60 years. For his own mysterious reasons, he decides to hitch a ride in the battered RV of Clive (Frost) and Graham (Pegg). The two men and an alien go on a road trip, hoping to reunite Paul with his mothership. Along the way, they meet a variety of strange characters, accidentally kidnap a woman, and are pursued by government agents hoping to recapture the little green guy. Worlds are rocked. Stuff blows up. And Clive and Graham will never, ever be the same.

If this sounds Spielbergian, you're right on the mark. Pegg, Frost, and Mottola freely admitted Spielberg's influence was all over Paul, and that they had happily lifted inspiration and ideas from the director while they worked together on The Adventures of Tintin. There was even wistful talk of having John Williams score the film if the budget could only allow it. But unlike the gentle E.T. or the silent beings of Close Encounters of the Third Kind, Paul is a free-thinking and outspoken character with a profound influence on everyone he comes across. "Seth's analogy [of Paul] was: Eddie Murphy in Beverly Hills Cop, and Simon's is Ferris Bueller," says Mottola. "He's not that guy who changes, he changes the people around him. He's actually quite fine the way he is. He's just sort of a catalyst for a bunch of people who are a bit repressed or need to come out of their shell or whatever, and he affects them. He's actually quite a liberal guy. And there's some stuff in this movie that hopefully you all think will be kind of cool for a mainstream film. It pushes some buttons about Christianity and stuff like that, that I think we can sneak in because he's a fantasy character and you can say those things with a guy who's not real. If one of your favorite comics got up in a movie and started preaching about atheism, it might ruffle some feathers. But I think we can let our little alien guy say a whole bunch of things that are kind of provocative."

It's a film that's making a decided effort to distinguish itself from Pegg and Frost's collaborations with Edgar Wright. References to Shaun of the Dead and Hot Fuzz were cut, though the sharp-eyed will notice Shaun and Hot Fuzz cosplayers in the SDCC scene. "Edgar has insisted, and quite rightly, that this film never be sold as part of the box set with our other two films," says Pegg. "I think Edgar's right. This has to be seen as something different. This is mine and Nick's. We've written this together, it's a different director. Same production company, but we want it to feel like it's a different thing. You know, obviously the temptation is to see it as [part of the Blood and Ice Cream trilogy] because it's Nick and mine."

"Obviously Edgar would have done a brilliant job and would have done something completely different with it, but probably that's why Edgar didn't want to do it," says producer Nira Park. "And obviously we talked to Edgar about it when we first had the idea, and it was never going to be something that Edgar wanted to do because it's not really his sensibility as much as Scott Pilgrim and other things that he's developing." Wright may not be present, but his spirit by way of his new property is – it won't take the sharp-eyed to notice the enormous Oni Press Scott Pilgrim display on the SDCC set. (Incidentally, I tried to buy Vol. 1, but the Oni vendors would have none of it!)

So, now you know as much as we do about Paul. Since the titular character was to be created in post-production, we left without any idea as to what he will actually look like. We'll find out at the same time as you, when life imitates art with the Paul panel at this year's ComicCon. The first footage will premiere, and with it our glimpse at the mysterious and life-changing extraterrestrial. Who knows? Maybe the footage will even contain our Hall H scene, which will create a vortex of eeriness that will haunt us online journalists for years to come. I hate to be dramatic, but just a day spent at the miniature con left me dreaming of walking the real SDCC floor in an endless loop, occasionally passing Pegg and Frost, but inevitably trapped by Sideshow Collectibles and Slave Leias. Just who and what was Paul? And why had he put me here for all eternity? I'll only find out by returning to the scene of San Diego. Save me a seat on Saturday!