When Tina Fey wrote the screenplay for Mean Girls, she based the plot on Rosalind Wiseman’s 2002 bestselling self-help book, Queen Bees & Wannabes: Helping Your Daughter Survive Cliques, Gossip, Boyfriends & Other Realities of Adolescence. What made the 2004 high school comedy so, well, fetch, however, were the personal touches Fey added from her own life. In fact, the story of naive, formerly homeschooled transfer student Cady Heron (Lindsay Lohan) navigating the travails of teen life at the hands of queen bee Regina George (Rachel McAdams) and her army of “Plastics” — comprised of Gretchen Wieners (Lacy Chabert) and Karen Smith (Amanda Seyfried) — may have been filled with Fey’s experiences as much as Gretchen’s hair was full of secrets.

“I revisited high school behaviors of my own — futile, poisonous, bitter behaviors that served no purpose,” Fey, a graduate of Pennsylvania’s Upper Darby High School — and admitted former “mean girl” herself — once recalled to the New York Times. “That thing of someone saying 'You’re really pretty' and then, when the other person thanks them, saying, 'Oh, so you agree? You think you’re pretty?' That happened in my school. That was a bear trap.”

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Regina George's famous compliment is inspired by Fey's mother

That line, of course, was delivered by the ruthless Regina, a character that was further shaped by another member of Fey’s household: her mother, Zenobia “Jeanne” Fey. In one of the Mark Waters-directed film’s memorable moments, Regina compliments a classmate’s “adorable” outfit in the hallway, telling her, “Oh my god, I love your skirt. Where did you get it?” After the visibly flattered girl walks away, however, Regina turns to Cady and scoffs, “That is the ugliest effing skirt I’ve ever seen.”

The scene was straight from Jeanne’s playbook. "My mom has this habit that if she sees a lady in a really ugly hat or a glittery sweatshirt, she'll go 'I love your shirt' and I'll say 'Mom, that's really mean,'" Fey revealed in an interview. "And she'll say 'Clearly she wanted someone to notice that shirt. She picked it out. It has a huge Teddy Bear on it.'"

Mean Girls
Rachel McAdams as Regina George, Lacy Chabert as Gretchen Weiners and Amanda Seyfried as Karen Smith in ’Mean Girls’
Photo: Paramount/ Courtesy Everett Collection

Cady Heron was named after Fey's college roommate

Highly quotable dialogue aside, even the names of several of the movie’s characters came straight from the Saturday Night Live alum’s past. When Fey was a drama student at the University of Virginia in the early ‘90s, she shared an apartment in Charlottesville with a friend named Cady Garey, who, per UVA’s alumni magazine, is the namesake for Lohan’s protagonist.

Glen Coco is the real name of Fey's brother's friend

As for Glen Coco, the infamous recipient of four candy cane grams (“You go, Glen Coco!”), he was named after a friend of Fey’s brother, Peter. “I tried to use real names in writing because it’s just easier,” she later explained. “My older brother’s good friend is Glenn Cocco. He’s a film editor in Los Angeles, and I imagine it’s a pain in the butt for him. Someone said to me, you could buy a shirt at Target that says ‘You go, Glen Coco!’ That was unexpected.”

The real Janis Ian is a musician who performed on 'SNL'

Music aficionados are also likely aware that not only is Janis Ian (portrayed in Mean Girls by actress Lizzy Caplan) a real person, but the Grammy-winning singer also has a famous SNL connection. When the NBC sketch comedy series premiered in 1975, Ian was the show’s very first musical guest. Not only that, her 1975 song “At Seventeen” can be heard playing in the background during the movie, as well. And let’s not forget that among the movie’s cast were Fey’s SNL colleagues Amy Poehler, Tim Meadows and Ana Gasteyer. (The show’s creator, Lorne Michaels, also served as a producer for Mean Girls.)

The movie's relatability is 'this little net that catches girls'

As far as Wiseman was concerned, Fey’s vision was the only one that she felt could do her book justice. “People had called about turning it into a movie or a TV show, and I had no problem turning them down because it was always something cheesy,” Wiseman once said. “Then Tina called… I knew it was important to her that it was not going to be stupid.”

She continued, “I’ve found a lot of success in my life by collaborating with women who are smart and funny, and Tina fit that category. From the time I said yes until the time it came out was about 18 months.”

Now, more than a decade after the film’s release, its legacy — and cult following — continues to transcend the tests of time. The reason, according to Fey, is Mean Girls’ universal relatability. “It has this little net that catches girls as they pass through preteen and high school age,” Fey has said. “Girls will come up to me and say it helped them get through a terrible year.”