The Big Bang Theory has brought a lot of joy to its fans over the 12 years of its airing.
However fans of the show have always been adamant they have wanted to figure out the finer details left out of the mainline episodes.
One of the biggest mysteries surrounding the show has been that of Penny’s (played by Kaley Cuoco) surname.
There are a number of theories surrounding Penny’s elusive name, but it looks like actress Kaley has known all along.
According to Screen Rant, Kaley spoke to CBS News back in 2017 and revealed she knew Penny’s surname.
To make matters worse, she went on to say she didn’t want to reveal the name at all.
She told the publication: “It’s kind of a personal thing.
“It feels like a jinx. We haven’t said it for so long. I feel like if we said it, the world would explode.”
While it certainly wouldn’t make the world explode, fans are still dying to find out what her name is.
Unfortunately, now that the show has come to an end, it seems unlikely for the name to be revealed.
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Meanwhile, fans of the show have begun starting new theories about why the beloved character doesn’t have a surname.
Most recently viewers have begun suggesting that Penny is not her first name, but in fact a stage name.
Fans of the franchise will know Penny arrived in Pasadena from Nebraska to become an actress.
But when she meets Leonard Hofstadter (Johnny Galecki) and Sheldon Cooper (Jim Parsons) she was very much a struggling actress.
As many actors do, Penny may have adopted the name viewers now know her by in an attempt to raise her chances of being hired.
However, there are not any real ways of proving this outrageous theory.
What’s more, Penny’s name did eventually change to Penny Hofstadter after she married Leonard, so it almost certainly had to have been her real name.
This fact, combined with the news that Kaley did know the surname all along, certainly cement the character’s name was originally planned out.
But will viewers ever find out the truth about Penny?
The Big Bang Theory season 12 is available on CBS and All4.