'Big Bang Theory' Book Reveals Who Almost Played Penny Instead Of Kaley Cuoco

Kaley Cuoco in 2019 (Photo: Rich Fury via Getty Images)

Penny, the sunny, naive Cheesecake Factory waitress on “The Big Bang Theory,” was almost a “cynical, down on her luck” character named Katie.

A new excerpt from journalist Jessica Radloff’s upcoming book, “The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series,” was published in The Hollywood Reporter on Thursday. The sampling centers around the development and casting of the beloved and bubbly Penny, who was eventually played by Kaley Cuoco.

According to the cast and crew interviewed for the book — which acts as an oral history of the CBS comedy — Cuoco was initially rejected for the role.

Sheldon (Jim Parsons, right) and Penny (Cuoco) share intimate secrets in an episode of “The Big Bang Theory.” (Photo: CBS Photo Archive via Getty Images)

Radloff writes in her book that the show’s female lead was conceived as a darker and more worldly character. She was originally called Penny, but because CBS had another pilot at the time featuring a character with this name, the network asked for a change. So, the character was renamed Katie, and the upbeat Cuoco just didn’t fit her vibe.

“I know Chuck [Lorre, a co-creator of the show] really wanted me for the role of Katie, and I was definitely bummed when I didn’t get it,” Cuoco told Radloff. “But I kind of have a way of moving on because you have to.”

Marisa Tomei was a potential pick for the character Katie. (Photo: Gregg DeGuire via Getty Images)

Radloff goes on to explain that actor Marisa Tomei was very close to getting the role of Katie and actually auditioned with the series’ lead, Jim Parsons. 

“Oh my gosh what a different world that would have been,” Parsons told Radloff.

“Tara Reid also came in for the role of Katie, and I think Elizabeth Berkley went to network for the role, too,” co-creator Bill Prady said of the “American Pie” and “Saved by the Bell” stars, respectively. Paddy added that Berkley, who also starred in “Showgirls,” was “terrific” in her audition.

Jodi Lyn O'Keefe in 2016 (Photo: Vincent Sandoval via Getty Images)

Jodi Lyn O’Keefe, best known at the time for movies like “She’s All That” and “Whatever It Takes,” ended up scoring the role of Katie for the pilot.

O’Keefe went in for a table read with the entire cast, and although everyone felt it went well, producers thought something was off. Parsons told Radloff that he thought O’Keefe was “great” during the read-through and that he was “stunned” to find out she got fired just 30 minutes later.

To learn who got the role next, head over to The Hollywood Reporter — and to find out how Cuoco eventually landed the part of Penny, check out Radloff’s book, due out Tuesday.

This article originally appeared on HuffPost and has been updated.