“Mean Girls” Secrets in New Book About the Making of 2004 Film: From $10K Wigs to Twerking at Cast Parties

The book 'So Fetch: The Making of Mean Girls (and Why We're Still So Obsessed with It)' is out now

The limit to fun facts about Mean Girls does not exist.

Fans of the hit 2004 comedy get more behind-the-scenes tidbits, plus all-new cast and crew interviews, in the new book So Fetch: The Making of Mean Girls (and Why We're Still So Obsessed with It) by Jennifer Keishin Armstrong, who is also behind books about Sex and the City and Seinfeld.

The unauthorized Mean Girls making-of book is billed as "part love letter, part cultural commentary," which brings up little-known secrets about the Tina Fey-penned project — like how it was originally titled Homeschooled.

Read on for some of the groolest discoveries featured in So Fetch, which is available now wherever books are sold.

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Blake Lively, Kristen Stewart, Megan Fox and more were considered for Mean Girls roles

The Plastics and key players of North Shore High almost looked very different. Of course, the iconic roles ultimately went to Lindsay Lohan as Cady, Rachel McAdams as Regina, Amanda Seyfried as Karen, Lacey Chabert as Gretchen, Lizzy Caplan as Janis, and Daniel Franzese as Damian.

But according to the book, which includes interviews with casting director Marci Liroff, Ashley Tisdale, Vanessa Hudgens and Mary Elizabeth Winstead all auditioned for Gretchen.

When Lohan, 37, expressed early on that she'd rather take the Regina role, the filmmakers considered alternative actresses for Cady, including Kristen Stewart, Mae Whitman and Michelle Trachtenberg, according to the book.

Related: See the Mean Girls Casts Side-by-Side with the Other Actors Who Played the Characters

Actresses like Haylie Duff, Kate Mara, Blake Lively and Leighton Meester tried out for the now-iconic role of Karen, as did Lohan's Confessions of a Teenage Drama Queen costar Megan Fox.

Meanwhile, America Ferrera and Kat Dennings circled for Janis, the outcast who's out for revenge against teen queen Regina.

Penn Badgley, Jared Padalecki and Max Minghella all auditioned to play heartthrob Aaron Samuels. That role went to Jonathan Bennett — after another unnamed actor was cut from the role immediately after a cast table read.

Related: Lindsay Lohan Asked to Be Regina George in Mean Girls: 'I Wanted to Play a Pretty, Normal Girl'

Rachel McAdams' Regina wig cost $10,000

There's a shred of truth to the famous Mean Girls line of dialogue that Regina George's hair is rumored to be "insured for $10,000." According to So Fetch, which features an interview with hairstylist Carol Hartwick, the long, blonde wig worn by McAdams' Queen Bee cost about that much.

The hairpiece, per the book, was manufactured by a wigmaker in Stratford, Ontario. (Mean Girls was filmed mostly in Canada).

Also, Chabert, 41, "wore a three-quarters wig to make her big hair happen, pumping up her naturally fine strands," the book details. Her gossipy Gretchen famously sported a hairdo "so big" because "it's full of secrets."

"Hair was important [on the movie]," says Hartwick in the book. "I was never so busy."

Related: Reneé Rapp Explains Her 'Love' for Regina George: 'The Mean Girl Is Always Hot to Me' (Exclusive)

The Glen Coco actor got the part after stumbling onto the set

So Fetch offers insight into how many of the background actors landed their parts, especially those memorable one-liners that have forever cemented them in pop-culture history. It also gets into their experiences making the movie — and the viral online attention they've gotten in the years since.

David Reale had an uncredited role as Glen Coco, the subject of Damian's famous Santa-costumed candy-cane line: "Four for you, Glen Coco! You go, Glen Coco." Reale happened into the iconic brief role by accident.

"No one on the Mean Girls production team knew his name. He had signed no contract to be in the film. He had just shown up," Armstrong writes.

The actor, then 19, had already auditioned for the film and didn't make the cut. Reale went to the set to visit friends, when director Mark Waters saw him randomly and said, "I'm gonna get you in the next scene. And you're gonna have a name and everything. It's gonna be great."

Related: The 10 Biggest Differences Between the New Mean Girls Movie and the Original

The Mean Girls wrap party featured twerking and karaoke

To celebrate the completion of filming, the cast and crew let loose at a big party. Some of the cast members recalled memories from the event in So Fetch.

Jill Morrison, who had a small part as the Crying Girl, says in the book that she did shots with Fey, 53, and costar Amy Poehler. "Morrison danced with them, freaking out when she saw Poehler do a little twerking move like she'd done during a Saturday Night Live sketch once," reads a line in the book.

When karaoke began at the gathering, Nicole Crimi (the young actress who played Regina's little sister) sang a song with the Plastic actresses, while Franzese and Poehler sang "Love Shack" by The B-52s.

The cast of the new 2024 Mean Girls movie musical similarly had a blast at their wrap party. Auli'i Cravalho, the new Janis, told PEOPLE they all were "having a great time, kind of rocking on the dance floor" at the celebration, which was "so much fun."

Damian actor Jaquel Spivey added, "To have all of us in a room having some drinks, listening to some Beyoncé, shaking a little ass, was such a fun time."

Related: Tina Fey, Maya Rudolph and Amy Poehler Have Mean Girls Reunion at the Movies

Mean Girls narrowly avoided an R rating

When handing down its ratings for the original film, the Motion Picture Association had some misgivings about their ability to award it a teen-friendly rating.

Fey and the filmmakers had to tweak some jokes to appease the ratings board, in order to get the PG-13 rating that would help target a younger audience. For example, instead of a rumor that a character masturbated with a frozen hot dog, they had to go with "made out" with a hot dog.

In another instance, an insult of "vag odor" was swapped with "fat whore." And the moment when a boy asked Cady whether her "muffin" is "buttered" was originally, "We're taking a lunchtime survey: Is your cherry popped?"

Related: Mean Girls Cast: Where Are They Now?

The team pushed back on one request though. Fey "wrote an impassioned letter to the board explaining why she thought the cut was sexist," in regards to the MPAA wanting the "wide-set vagina" moment removed, the book reports.

"They were going to fight this one. That line was too good to lose, especially with the frozen hot dog already nixed," Armstrong says in the book. "... It worked. The board reversed its decision on that line, and that line alone."

Mean Girls ultimately received a PG-13 rating for "sexual content, language and some teen partying." (The new movie-musical version is PG-13 for "sexual material, strong language and teen drinking.")

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