Many of us have been there: belly hanging over our pants like a muffin top; an acne-ridden face harboring more oil than OPEC; hormonal confusion yielding enough embarrassing moments to fill Tara Reid's diary. Nobody said being a teenager was easy.

To most, these are simply horrific reminders of the high school days they're all too happy to have left in life's rearview mirror. For the cast of "Just Friends," however, zits and braces and extra rolls of fat instead spur fond remembrances of times they wished would never end.

"This whole movie was just so great, working in this city where you're just sort of locked away and there's nothing really to do but just spend time with each other," Ryan Reynolds remembered of "Just Friends," an irreverent romantic comedy filmed in the remote Canadian towns of Regina and Moose Jaw. "Thankfully, there were no conflicting personalities; everybody loved each other and we were actually sad to leave."

Doubling for snowy New Jersey, the set saw temperatures dip 50 degrees below zero while serving as a temporary home to Reynolds and co-stars Amy Smart, Anna Faris and Chris Klein. With the film's plot concerning Chris (Reynolds), a formerly fat high school loser returning home a decade later to seize the love of former friend Jamie (Smart), Reynolds and crew found themselves with one prop that easily helped them pass the time.

"It was the best first day of filming," Smart remembers of seeing Reynolds transformed into the overweight high school version of his character. "He was in his suit, and he was trying all his mannerisms, and he almost reminded me of 'Mrs. Doubtfire,' I mean with his chins and his afro."

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"That fat suit," Reynolds laughed. "The thing that blew me away was how real it looked, because I would see regular civilians on the street and they would have no idea that I was wearing makeup. ... A woman asked me when we were shooting — I was standing outside the set — and she asked me if Ryan Reynolds was inside."

Asked about his response to the woman, Reynolds smiled slyly. "I said, 'Oh, he's inside, all right.' "

A similar transformation overcame Klein, the "American Pie" veteran known for his beefy build and cover-boy looks. For the film's flashbacks, Klein was buried beneath a facade of acne and long hair while becoming dorky Dusty Dinkleman, another potential Amy Smart suitor who competes with Reynolds both in the past and present.

"I kept saying, 'Longer hair, longer hair, more zits, more zits — make it really despicable,' " Klein recalled, insisting that he too enjoyed the chance to get ugly. "Eventually I won out and poor, poor Dusty Dinkleman didn't have a chance."

Reynolds may have been walking around the set 100 pounds heavier, and Klein may have resembled a pepperoni pizza rather than a leading man, but neither of the stars got quite as ugly (or quite as proud about it) as Faris.

"[She's] a little bit of all the pop icons mashed into one, but she might be a little bit crazier," Faris said of her breakout performance as Samantha James, a dim-bulb superstar who makes Paris Hilton look like Jackie Onassis (see "A Pop Diva Is Born In 'Just Friends' — And She Feels Awfully Familiar").

With director Roger Kumble ("The Sweetest Thing") promoting an improv-heavy film shoot, the comedic veteran of the "Scary Movie" films allowed Samantha's uncontrolled id to take over. "Kissing Ryan with the toothpaste," she said, naming her favorite off-the-cuff take. "That was me. I don't think he knew what was coming, and I just really get him. I mean, that toothpaste was all over the place."

"That's something that I will not quickly forget," Reynolds laughed. "Yeah, she sneaks up behind me with some toothpaste [pouring from her mouth] in this scene where she's all hopped up on painkillers and it's just an ugly mess; I didn't really see it coming."

"It was real toothpaste," Faris revealed, grimacing. "It was awful, it burned my mouth. It was terribly hard to not gag on that."

To the "Just Friends" stars, drooling toothpaste was but one of the ugly things they were willing to do for a laugh. And when the cameras stopped rolling, they were just happy to know that they were now closer to the movie's "10 years later" heroes than their high-school-flashback zeros.

"Pre-pubescent braces, bad news," Klein remembered of his youth. "Being short, skinny, having a soprano voice and braces at the same time. That was tough, and being a late bloomer made it even tougher to deal with, but I got over it somehow."

"I was a very late bloomer, so when I was 16 I looked like I was about 11," Faris admitted. "I had braces and headgear, and I was kind of a wreck. I wore glasses, and I had a very odd sense of style."

"I wore a cape to school for a while," she laughed, shaking her head. "I was a nerd. I was president of the drama club, which at my school was not the coolest thing to do. [The cape] was a Christmas tree skirt."

Asked to name something about herself that has changed over the years, Smart laughed and said, "My nose. No ... I was more of this hopeless romantic in my head; I just wanted this love and romance and boyfriend, and I was just boy-crazy."

Reynolds sympathized with Smart's unrequited love. "Yale Greene," he giggled, naming the real-life teenage girl who insisted they just stay friends. "She gave me the Heisman."

"I was just absolutely head-over-heels in love with her," Reynolds admitted. "She was like a bit of a tomboy, and everybody loved her, and she was so much fun and she wasn't like a princess or anything like that. She was just that girl who managed to find that middle ground that everybody dug.

"I just became her good buddy, and it just killed me," he laughed uneasily. "Literally, every day it was just this mini-hyper-death, and it was terrible. It's something I wouldn't wish on my worst enemy, because it's that heartsick feeling when you're in the halls at school and you're walking down certain halls hoping to run into her. It's an ugly cycle."

Now life imitates art as Reynolds is rich, handsome and a decade away from the girl who dissed him. Noticing the role reversal, the actor admits that it would be nice if his portrayal of high school awkwardness would turn Greene into the one who's left longing. "I wonder if she would even think that," he smiled.

"I mean, she knows I was absolutely in love with her, so I wonder," said the movie star. "I wonder if she might see ['Just Friends'] and not see some of us in there."

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