Now thatThe Big Bang Theoryis over,Kaley Cuocois spilling all the secrets.

Cuoco appeared alongside herBig Bang Theorycostars on The Late Show with Stephen Colbert on Thursday following the series finale of the hit comedy. After dishing on what they’d taken from set and which other character they’d like to play, Cuoco was asked the question fans have been pondering for the last 12 years: What is Penny’s last name?

“You’ll never know,” she joked, before confessing, “There really is no answer.”

Cuoco reveled that Penny was never given a last name and after a few seasons, the decision was made to keep it that way.

“She’s Cher — one name!” Cuoco said. “It became a little superstitious for me, too.”

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Jim Parsons, who starred as Sheldon on the series, said he never realized she wasn’t given a last name.

“We don’t even call your parents Mr. and Mrs. anything,” he said. “I never noticed this!”

After 12 seasons,The Big Bang Theorycame to a close on Thursday night, with back-to-back episodes that wrapped up several long-running storylines for the beloved geeks.

Series regulars Leonard Holfstadter (Johnny Galecki), Sheldon Cooper (Parsons), Penny (Cuoco), Howard Wolowitz (Simon Helberg), Amy Farrah Fowler (Mayim Bialik), Bernadette Rostenkowski-Wolowitz (Melissa Rauch), Rajesh “Raj” Koothrappali (Kunal Nayyar), and Stuart Bloom (Kevin Sussman) were all there, each getting their own versions of their happily ever afters.

The night started with an episode titled “The Change Constant,” before moving to the final episode, “The Stockholm Syndrome.”

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THE BIG BANG THEORY

Filming for the episode happened on April 30. The last scene of the whole series was pre-taped, and hidden not just from the studio audience, but also from the entire cast.

“It seemed like a nice thing for us to hold back one piece of the finale, so there’s at least one thing that couldn’t be spoiled,”showrunner Steve Holland previously said. “That way it will also make the night extra special for those who were at the taping because there’s an extra piece.”

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“I actually can’t, to be honest,” said Cuoco, 33. “I can’t really picture it. And I don’t think there really will be my life without it — I think it’ll always be there, I think it’ll always be running, I think we’ll always have those fans. It’s always going to be a part of me.”

Nayyar, 38, said the ending would be “very sad.”

“I grew up on this show — I was a kid out of grad school,” he said. “I don’t even know how to comprehend that.”

The Late Showairs weeknights at 11:35 p.m. ET.

source: people.com