The Big Bang Theory: The Unaired Pilot Change That Made Penny Possible

Penny is one of the most important characters on "The Big Bang Theory." Played by "The Flight Attendant" star Kaley Cuoco, Penny provides more than just entertainment value in the sitcom; for one, she helps Sheldon (Jim Parsons) and Leonard (Johnny Galecki) develop their social skills and ultimately live fuller lives. Of course, there's a fun appeal to the juxtaposition of Penny's character — an aspiring actress and Cheesecake Factory waitress — in comparison to her academic neighbors. However, that wasn't always the case. 

During an appearance on "Dinner's On Me With Jesse Tyler Ferguson," Parsons discussed changes made to the original "Big Bang Theory" pilot, and one of them would have made Penny a totally un-viable character. "They didn't get the character that Kaley ultimately played right the first time," he revealed at the 9:55 mark.

There are a lot of things "The Big Bang Theory" fans might not know about Penny, and one may be just how many rewrites the character went through during the pilot episode. Originally, when she first met Sheldon and Leonard, she was a savvy, street-smart manipulator, rather than the kind-hearted girl from the Midwest fans are used to. "It was done in a much more vicious way like in the original pilot Leonard and Sheldon come across her crying on the corner ... boyfriend's dumped her or whatever and like she kind of lassos in, kind of puts one over on us in order to have a place to stay," Parsons elaborated. 

From the sounds of it, there wasn't a believable, heartfelt connection between the three main characters, which is ultimately what makes the show work. The show was also supposed to be set on the East Coast, which wouldn't have made sense for Penny as she moved from Nebraska to California to become an actor.

Chuck Lorre and Bill Prady may have created "The Big Bang Theory," but Kaley Cuoco deserves a lot of credit for shaping Penny into the character so many fans have come to know and love. "In the first pilot, the female character is kind of rough. She's dangerous in a way and wasn't very nice to the guys," Prady recalled to Entertainment Weekly. And the test audience who watched that first pilot was not impressed with the original Penny; in fact, they hated her. 

This all happened before Kaley Cuoco arrived on the scene. The street-smart East Coast version of Penny was actually called Katie, and she was played by a completely different actor. Amanda Walsh, who later ended up working as a writer on "Schitt's Creek," had the job of bringing Katie to life, but ultimately, her version of the character just didn't work. Walsh has since admitted that being recast was tough to deal with.

However, she was glad that the show moved in a completely different direction from what had been set out in her pilot script. "The fact that it wasn't immediately picked up and there was such retooling made it an easier pill to swallow," she said in "The Big Bang Theory: The Definitive, Inside Story of the Epic Series." While it's easy to wonder what if, there's no denying that "The Big Bang Theory" would have been a very different series without Cuoco as Penny — and who knows if it would have lasted 12 seasons without her.