Jim Parsons Recalls This Actress Nearly Starring in The Big Bang Theory Over Kaley Cuoco

This news will make you say, "Bazinga!"

According to an upcoming Big Bang Theory oral history, fan favorite actress Kaley Cuoco nearly didn't nab a leading role at all. The book reveals that the pilot originally featured a female lead called "Katie" who was the antithesis of Cuoco's Penny. Instead of being a Midwestern optimist, Katie was "cynical, down on her luck, and off-putting," according to an Oct. 6 article from The Hollywood Reporter.

And who was in line to play Katie? While Cuoco auditioned for the role, it wasn't given to her because she was too bubbly. Instead, Jim Parsons read with actress Marisa Tomei while she was auditioning for the part.

"I read with Marisa Tomei," Parsons shared in the book. "I remember going to the snack room after we were done and telling [casting directors] Ken [Miller] and Nikki [Valko], 'I've never been in someone else's audition before!' And they said, 'Well, she was kind of really auditioning you.' And I went, 'Oh, that makes sense.' But oh my gosh, what a different world that would have been."

American Pie's Tara Reid and Saved by the Bell's Elizabeth Berkley went up for the role as well. But the part of Katie ultimately went to Amanda Walsh after another actress, Jodi Lyn O'Keefe, did an unsuccessful table read and was thought to have brought a "darkness" to the role that didn't work, according to Valko.

The Big Bang Theory Cast: Then and Now

The original pilot, which also starred Iris Bahr in the role of "Gilda," a fellow scientist harboring a crush Johnny Galecki's Leonard who once had sex with Sheldon at a Star Trek convention, was ultimately scrapped and reworked without Katie and Gilda.

And this isn't the only Big Bang Theory on-set secret that's been revealed by the upcoming oral history, The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series by Jessica Radloff. Cuoco and Galecki quietly dated from 2008 to 2010, and recalled their romance in the new book.

"All the scenes up until we actually got together in real life, it was obvious there was always something there," Cuoco shared. "There was chemistry, and we were crushing on each other. That was the whole first season until we actually got together for real."

Kaley Cuoco, Marisa Tomei
David Livingston/Getty Images, Albert L. Ortega/Getty Images

For more behind-the-scenes details, check out The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series, which comes out Oct. 11.

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