Kaley Cuoco Is Keeping This One 'Big Bang Theory' Secret to Herself

08/31/2017 04:09 pm EDT

Whether big or small, every TV show has its own set of mysteries. The Big Bang Theory is no exception.

For 11 years now, fans of the long-running CBS sitcom have labored over one detail that has never been released.

"What is Penny's last name?!"

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With the exception of Penny, every character on the show has always had a first and last name. For whatever reason, Penny never did.

Now, having married Leonard, the character does carry the last name of Hofstadter, but that doesn't stop fans from wondering what her maiden name is.

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During the Big Bang panel at this year's San Diego Comic-Con, the floor was open to questions from fans. One of these fans asked Kaley Cuoco if she knew Penny's maiden name.

"In my head, I have one, but now I am Hofstadter. So it is like Cher at this point. So, Im not telling."

While Penny was never given an official last name by the writers, Cuoco came up with one on her own. This isn't exactly uncommon for actors, especially those who have had certain roles for an extended period of time. Many performers will give their characters backstories and fill in details that may have been left out by the creative team.

So, Penny does have a last name, but it doesn't look like Kaley Cuoco is going to spill the beans any time soon.

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