The Big Bang Theory enjoyed a lengthy run lasting over a decade. Although the show was a hit, like other sitcoms, it was judged for some questionable episodes and storylines. In the following, we're going to take a closer look at the moments that are most regrettable, especially from the standpoint of those working behind the scenes.

We're also going to take a closer look at scenes that the cast regretted. In fact, Kaley Cuoco wanted a certain Big Bang Theory scene removed altogether. We'll take a look at why Cuoco wanted the scene gone from the show, and how Chuck Lorre agreed, but still went through with it.

Finally, we'll reveal which Big Bang Theory scene actually got the boot from the show, and it takes place at the very beginning during the pilot episode.

The Big Bang Theory Creators Revealed There Were Several Storylines On The Show That They Regretted

Kaley Cuoco and Kunal Nayyar
A photo of Kaley Cuoco and Kunal Nayyar sitting on the couch in Penny's apartment during The Big Bang Theory.
via CBS

Although The Big Bang Theory enjoyed success for 12 seasons, the showrunners didn't enjoy every episode or storyline. In fact, Steve Molaro lost sleep over a certain cliffhanger moment that ended season 4.

Lorre proposed a shocking ending to the season, and it featured Raj and Penny sleeping together. Molaro instantly hated the idea, and spent the entire time off thinking about ways to reverse the storyline once the show restarted.

"I really did not like that season finale ending,” Molaro admits.

“I spent the entire hiatus being upset about it… I went upstairs to [Lorre’s] office right when we got back to work [on Season 5] and said something like, ‘This is really bothering me. I think I have a way that we can… get out of it and preserve the characters as they are.’ He didn’t love it, but he knew it was important to me to the point that he conceded."

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Among other storylines the cast wasn't into includes Raj's quietness around women. Kunal Nayyar grew frustrated that he couldn't contribute to certain scenes because of it. Simon Helberg also grew tired of Howard's sleazy ways, and preferred his character when he met Bernadette.

Kaley Cuoco Hated The Serial Apeist Storyline And After The Fact, Chuck Lorre Admitted It Was A Bad Idea

Kaley Cuoco absolutely hated The Serial Apeist storyline. Not only did she hate the context, but she also despised all the makeup she had to wear for the scene. Cuoco actually proposed for the scene to be removed completely, but it was not meant to be.

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She revealed with TV Line, “The worst experience was filming Serial Apeist and getting covered in hair from head to toe,” she says. “I was like, ‘Really, you guys? This is what’s happening?’ And Chuck just thought it was so funny. He loved it. I never understood why.”

Although Lorre might've enjoyed it at the time, he revealed otherwise looking back at how the scene played out.

"We wanted Penny to have some small success in her from of being a successful actor, but it’s not my favorite episode,” he explains.

“Doing a show within a show — writing the ‘bad’ scenes that she’s in an otherwise good show — was not our finest moment. The goal was legitimate, which was to put her in a bad move and see her struggling to make something work.”

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At the very least as TV Line pointed out, the episode did have some context as Penny would quit her acting career shortly after, for a new start as a pharmaceutical sales rep.

The Big Bang Theory Did Ban One Scene From The Pilot Given That It Didn't Make Much Sense For Sheldon And Leonard's Characters

Big Bang Theory cast
A photo of The Big Bang Theory cast on the red carpet posing for a picture.
via: Instar

One scene did get banned, and it took place at the very beginning. The original opening scene to The Big Bang Theory sees Sheldon and Leonard at the sperm bank and given their dialogue, it seems like the two are out of character.

Chuck Lorre admits that the scene was a mistake, and that the show has a different starting point.

“The scene was so wrong. In my mind, the show truly began with those awkward hellos between Penny, Sheldon and Leonard when she’s unpacking boxes in her apartment.”

Jim Parsons admitted that he wasn't bothered by the scene at the start, but looking back, he did reveal that it didn't make much sense.

“Looking back, it was out of place, but there was no way for the producers to know… Nobody knew who Sheldon was yet, so the live audience accepted it for what it was. But it is confusing information now, and I get why Chuck took it out of syndication, because the episode is much stronger and more special without it.”

Clearly, the episode was better with the omission.