Ashley Tisdale Recalls Mean Girls Screen Test with Blake Lively — and Ad-Libbed Line That Made Final Film!

Ashley Tisdale is looking back at one film role that nearly was.

During a visit to Watch What Happens Live with Andy Cohen on Tuesday night, the High School Musical actress opened up about screen testing for Tina Fey's 2004 comedy Mean Girls.

"Gosh, it was so long ago," said Tisdale, 38, when host Andy Cohen asked her about the audition, which she said was for the role of Karen Smith. "I just remember screen testing, and it was me and Blake Lively and someone else. But yeah, I screen tested. That was like, eons ago, obviously."

The role of Karen — described in Mean Girls as "one of the dumbest people you will ever meet" — would go on to be played by Amanda Seyfried, who at the time had been known in the soap opera world for roles in As the World Turns and All My Children.

Tisdale had more credits to her name, with a series of commercials, voiceover parts (including 1998's A Bug's Life) and guest spots in shows like 7th Heaven, Boston Public, Malcolm in the Middle, Still Standing and Beverly Hills, 90210. Two years after Mean Girls' release, she'd have her breakout, playing Sharpay Evans in 2006's High School Musical — a part she reprised in the beloved film's two sequels.

Lively, meanwhile, would go on to become part of another famous foursome in 2005's Sisterhood of the Traveling Pants. She became a household name in 2007, after scoring the part of Serena van der Woodsen in Gossip Girl.

Though Mean Girls wasn't in the cards for either actress, Tisdale's audition at least did leave an impact on the final film, she said on WWHL.

"I just remember I ad-libbed — because I always like in an audition to steal the scene — and I ad-libbed one line, and they put it in the movie," Tisdale remembered. "And I was like, 'Are you kidding me?' "

"I should have gotten a writer's credit," she joked. "I'm kidding, but I was like, 'Dang.' "

Cohen, 55, failed to ask Tisdale what line she was referencing, but as Mean Girls fans will tell you, many of Karen's lines are some of the most memorable from the film (see: "There's a 30% chance that it's already raining!").

Tisdale and Lively, 36, weren't the only stars who were considered for Mean Girls.

According to Jennifer Keishin Armstrong's 2024 book So Fetch: The Making of Mean Girls (and Why We're Still So Obsessed with It), though the iconic roles ultimately went to Lindsay Lohan (Cady), Rachel McAdams (Regina), Lacey Chabert (Gretchen), Lizzy Caplan (Janis), Daniel Franzese (Damian) and Jonathan Bennett (Aaron), a slew of other actors nearly napped the parts.

Casting director Marci Liroff told the author that Kristen Stewart, Mae Whitman and Michelle Trachtenberg were all considered for Cady, while America Ferrera and Kat Dennings circled for Janis.

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Liroff said Tisdale was actually up for Gretchen, alongside Vanessa Hudgens and Mary Elizabeth Winstead, while Lively, Haylie Duff, Kate Mara and Megan Fox went out for Karen.

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

Watch What Happens Live with Andy Cohen airs Sunday-Thursday evenings on Bravo.