enjoyed 12 seasons but in truth, there was a lot of uncertainty at the start. The original pilot failed, and a lot of external sources figured that would be it for the show. gave the series a chance to rethink its plotline, and a major move was adding the Penny character played by .

Kaley's contributions were massive, but the same can be said for in his role as Sheldon. The actor was on top of Hollywood thanks to his role on the series, and became the highest-paid TV actor in 2017. Although he enjoyed lots of success, things were different at the start. As we'll reveal in the following, Sheldon looked a lot different during the unaired pilot, and a lot of fans were not impressed.

Jim Parsons Was Stunned After The Katie Character Was Removed Following The Initial Unaired Pilot

could've looked very different. At the start, Sheldon and Leonard were forced to deal with an aggressive Katie character. Although both Jim Parsons and Johnny Galecki enjoyed Jodi Lyn O’Keefe's brief contributions to the show, she was ultimately released as fans just didn't like the way she treated Leonard and Sheldon.

At the time,

He recalls, "We did that table read, and I thought Jodi was great. Afterward, me, Johnny, Jodi and Iris were going to meet at some restaurant."

"Johnny texted me and said, “Hurry up, Jodi got fired.

” I mean, we had just done the table read thirty minutes earlier. Johnny, Iris and Jodi were already there when Jodi got a call from her agent saying she was being let go."

Parsons revealed that in terms of what the script involved, O'Keefe was on point with her delivery.

"I know when someone’s not good. And Jodi was . I was stunned. But they realized during that table read that the character’s approach to the other characters was too harsh, too whatever, even though Jodi, in my opinion, nailed what they had written."

The unaired episode was truly all over the place, and that was especially true for Sheldon's character early on.

Sheldon's Lines And Behaviors Were All Over The Place During An Unaired Pilot Scene

The scene sees the character Gilda discuss her intercourse session with Sheldon... not quite what fans would see in the later seasons, especially with Sheldon's relationship alongside Amy. Fans even see Sheldon pull off a smile when the information is disclosed.

Later on in the scene, Katie knocks on the door and sets up the rest of the episode. The only character that seems to be somewhat established is Leonard.

Fans couldn't get enough of the unaired scene, posted to in the video below.

Fans were particularly shocked at how different the actual pilot would be, and the massive change that were ultimately made.

One fan writes, "I love this pilot. Not because it's good but because it shows the extraordinary work that went into making this show a huge success. The actress is wonderful and I bet she could have played Penny...but I love who they eventually chose. She did exactly what was given to her though, so don't fault her for her character. The writers knew it had to go in a different direction. I love seeing how this show was molded into what it was/is today."

"Love the pilot, seeing this Sheldon after watching the original series, it's like watching an alternate universe and it's so cool."

The involvement of Penny proved to be a major game-changer in the pilot that eventually aired.

Kaley Cuoco's Involvement As Penny Was A Hugh Difference Maker For The Series

Kaley Cuoco was a major difference maker on Creators , and that was also true for the pilot. Especially in Leonard's case, his premise was completely different.

Lorre revealed, "When you think about it, the plot of the second pilot is pretty simple. Leonard meets an incredible woman, he's obsessed with her, she's the woman of his dreams, and he wants to win her heart. So, she gives him a task, he fails at it, and then they all eat dinner!"

Co-creator Bill Prady continues with

, "Leonard's struggle was always that Penny was like the outside world. She was like, come out dancing, come out and see things. And Sheldon, on the other hand, was like, come back in here, we have DVD commentaries to watch and we have Dungeons and Dragons to play."

Lorre would go on to admit that Penny was a major risk, given how different she was compared to the main cast of friends. Nonetheless, she proved to be the perfect fit.