Penny, played by Kaley Cuoco, became the heart of the show, but the character could be very different.
Fans of The Big Bang Theory know Penny as a sweet girl and the life of the party. But her fate could have been very different. In the very first pilot episode, a girl named Katie appeared, and she was not played by everyone's favorite Kaley Cuoco.
The original pilot episode was not well received by the test audience and was rejected. Initially, Penny's character was completely different and her name was Katie.
The role was played by actress Amanda Walsh and her character was far from cute and innocent Penny. The scene with Katie is still available to watch.
Thanks to Nina Tassler, who was the president of the network at the time, the character was completely redesigned.
In a scene from the first episode, Katie meets Sheldon and Leonard. She is arguing with her mother on the phone while sitting on a curb in the middle of the street. At this time, a famous couple is making jokes in their recognizable style.
After the episode was criticized, the producers completely overhauled the storyline and character of Katie, creating Penny instead.
In Jessica Radloff's book The Big Bang Theory: The Definitive, Inside Story Of The Epic Hit Series, Amanda Walsh revealed how she felt after her character was dropped from the show, which became one of the biggest hits in later years:
"It's never a call you wanna get as an actor, but Bill [Prady] was as nice as possible about the whole thing. And then I was really fortunate that a year later, Burrows hired me for another pilot […]. For me, that really validated the notion of "It's not you," because as an actor, you always question that."
While Kaley Cuoco became the star of the show, starring in all 12 seasons of the sitcom, Amanda Walsh starred in Two and a Half Men and Dirk Gently's Holistic Detective Agency.
Many fans feel that Penny should have been given a better ending in the show's final 12th season. Despite being one of the show's main characters, Penny still feels like one of the most unfinished and undeveloped characters in the entire series.
We never learn her last name, and her career – from waitress to aspiring actress to failed actress to pharmaceutical saleswoman – is confusing at best.
But the worst thing happened to her in the second half of the series finale. After spending the entire series expressing her lack of desire to ever have children, Penny learns that she is pregnant.
Source: The Big Bang Theory: The Definitive, Inside Story Of The Epic Hit Series