CBS seriesThe Big Bang Theorywill soon finish up its 12-year run, and the seven actors at its core are handling the change about as well as anyone could expect.

During Thursday’s episode ofThe Ellen DeGeneres Show,Kaley Cuoco— who was 20 years old when she first took on the role of Penny — told the host that she was “100 percent” going to cry during the talk show, adding that the cast only has nine episodes left to film.

AfterSimon Helberg, 38, who plays Howard, joked that he “didn’t know we weren’t coming back,” Cuoco recalled an emotional moment filming withJohnny Galecki, 43, who plays Leonard, before the holiday break.

“We’ve been getting super emotional,” the actress, 33, began. “We were just blocking, and we’re the only two in it, just kind of rehearsing the scene, and out of nowhere, I just started bawling.”

The Big Bang Theorycast.Michael Rozman/Warner Bros.

The Ellen DeGeneres Show

Cuoco continued: “The crew, the camera guys, they come out and they’re like, ‘We’re so glad you cried because we’ve been waiting to cry,’ and they all gave us this huge group hug, and we just all cried for like 10 minutes.”

In response, Jim Parsons, 45, who plays Sheldon, shared that he hasn’t shed any tears — yet.

“I have a very deep fear, seriously, that the most unexpected thing is going to happen and I’m going to absolutely lose my s— because it really is profound, the amount of time in your life,” he mused.

“It’s like more than any of us, I think, can get a grip on, and I’m worried it’s going to trigger something deep down like, ‘Oh, I didn’t know that was there! Oh, that hurts,’ you know?” he concluded.

Michael Rozman/Warner Bros.

The Ellen DeGeneres Show

“If anyone hugs me about it, I just start crying,” Cuoco quipped in response.

Galecki then shared how he’s coping.

“It still feels very hypothetical. I think like the end of this coming summer, when we generally would be meant to come back …” he said before Kunal Nayyar hopped in.

“When we’ll be unemployed, we’ll really be crying,” Nayyar joked.

The Ellen DeGeneres Show

ThenMayim Bialik, 43 — who previously starred in the NBC sitcomBlossom— recalled how she became involved in the series as Sheldon’s love interest, Amy, in its fourth season.

“I had never seenThe Big Bang Theory, I thought it was a game show,” she began. “Someone had told me that in some season … they mentioned the girl fromBlossomis a scientist, so when someone told me that, I thought it must be a game show, like a trivia thing.”

The Big Bang Theorycast.

The Ellen DeGeneres Show

Bialik continued: “I had no idea that it was a very popular sitcom, apparently … my manager said they’re looking for a female ‘Sheldon Cooper’ and I said, who’s Sheldon Cooper?”

Then an emotional Cuoco revealed that one big thing about the cast has never changed, no matter how popular the show became.

“When we started, you don’t ever think anything like this is going to happen,” she said. “What’s so sweet is even after all these years, and really up until recently … we come in, we’re like, ‘Did the show do well last night? Really? They watch? That person?’ And we kept that for so long, we never just kind of said, ‘We’re all good now.’ ”

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The show — which debuted in 2007, airs in syndication around the world, and has received 52 Emmy nominations and 10 wins to date — will conclude with 279 episodes.

The Ellen DeGeneres Show

In a joint statement, Warner Bros. Television, CBS and Chuck Lorre Productions said, “We are forever grateful to our fans for their support ofThe Big Bang Theoryduring the past twelve seasons. We, along with the cast, writers and crew, are extremely appreciative of the show’s success and aim to deliver a final season, and series finale, that will bringThe Big Bang Theoryto an epic creative close.”

“I actually can’t, to be honest,” said Cuoco. “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 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.”

source: people.com