'Young Sheldon' Stars, Producers Tease 'Show-Shifting' 100th Episode (Exclusive)

Iain Armitage, executive producers Chuck Lorre and Steve Molaro celebrate the 'Big Bang Theory' spinoff's milestone.

Young Sheldon is about to hit a milestone -- 100 episodes -- and the stars and producers recently stepped out to celebrate the CBS comedy's impressive achievement.

The series, a prequel spinoff to The Big Bang Theory, revolves around young Sheldon Cooper (Iain Armitage) as he grows up in East Texas. In the upcoming 100th episode, airing March 31, Sheldon gets an odd request from an old friend, Paige (McKenna Grace), while George Sr. (Lance Barber) and Mary (Zoe Perry) are caught in the middle of Meemaw (Annie Potts) and Dale's (Craig T. Nelson) breakup. 

"There’s definitely some big changes that come in that are going to take us through the rest of the season, some big reveals," co-creator/showrunner Steve Molaro told ET's Nischelle Turner on Friday at the 100th episode event in Los Angeles. "Once you see it, it ends on a show-shifting moment [and] I’ll leave it at that."

The cast was coy about the milestone episode, but all affirmed Molaro's intriguing tease.

"It’s good because you get a little upheaval in the episode," Perry confirmed. "There’s some twists and turns that people are definitely going to want to see where this episode ends and things really get shaken up in such a way that could have a ripple effect for all the season to come so it is fitting [for a 100th episode]. Very." 

Added Potts: "It's a good one. Anytime in this business when you get to 100, then you start going, 'Hmm, could we do 100 more?' I’m for it, I’ll keep going!"

"The episode is pretty chaotic," actress Raegan Revord revealed. "Georgie tells Maddie how old he is, chaos ensues. I mean, as it should in this episode and the rest of the episodes. Everyone is trying to figure out what Georgie and Mandy... what’s going to happen, you know? What’s going to happen?"

"It’s going to be very funny and it’s also going to be heart-wrenching, at times it’s going to be a bit dramatic sometimes," Armitage hinted. "But most of all, it’s going to be laugh-out-loud funny."

Armitage, who began the show when he was eight years old, looked back on the past five seasons and what it means to have the series reach this landmark moment.

"On 100th episode day, there's some pictures of me just with the stupidest face," he shared. "I’m just like, 'Haha, what? One hundred!' It’s crazy because it feels like we've only done one episode and at the same time it feels like we’ve done a thousand. I love it so much and I cannot wait to make more television and I can’t wait to work [with] these awesome people more and hanging out."

Robert Voets/CBS

The actor, now 13, said the secret to Young Sheldon's success is the "family dynamic." 

"We all have pretty good chemistry together and I think we do feel like a real family. Obviously being interviewed by ET is probably the very best," he quipped. "We’ve gotten along with each other from Day 1 and... it really does feel like a family. Of course we have really good writers who just make the best television. And without them I would just sound awkward, now I sound funny and awkward so it's even better comedy. But they’re the best."

His co-stars also reflected on the series' run-up to this point and expressed their gratitude. (The comedy has been picked up through season 7.)

"I am so grateful because it’s obviously such a testament to the producers and our show but to know that we're in that hallowed ground of reaching that pinnacle of numbers because so many shows don’t really get the opportunity or they don’t produce as many [episodes]," Perry said. "It feels like a very unique gift."

"It's pretty obvious that we are a spinoff of a really terrific show," Barber said. "Let's not forget that. This got us in the door. I think in five seasons though we've been able to garner some attention on our own merits as a different show and a different tone, et cetera. And we've allowed all of the viewers to fall in love with the Cooper family." 

"I’m a very chill and down-to-earth guy so now I’m just kind of realizing the position I’m in... and I’m very thankful for it but... I grew up watching people grow up on TV. I’m not used to being on the other side of that and I’m from Texas. I’m a normal kid so it’s kind of crazy to be on the other side of growing up on TV. It’s wild," actor Montana Jordan said.

"I’m so grateful because I literally love everyone on the show so much," Revord said. "They are the best people that I have grown up around cause I was eight or nine [when] I started and I’m now 14. It’s crazy to think that I was that little when we started and I’m 14 and all that time has gone past, like it feels like it flew by."

Wyatt McClure, who plays Billy Sparks, credited the show's success to Big Bang. "And how sad people were when it ended," he recalled. "It was very smart to make a spinoff of it and I think that's why fans love it so much 'cause it's basically Big Bang but basically 30 years before that." Matt Hobby, who portrays Pastor Jeff Difford, said it was the ability to balance the comedic with the dramatic seamlessly: "Really great jokes that everyone can get on board with balanced, with really heartfelt, tender moments about a family."

But co-creator Chuck Lorre and Molaro said the secret to Young Sheldon's success was finding Armitage.

"We don’t have a show unless we found Iain. If we hadn’t found Iain we wouldn’t be standing here today," Lorre stated, adding that the "wonderful" and "remarkable" thing has been that throughout "the whole journey, the entire cast has been a joy to work with. That gets said a lot but it’s often a smoke screen for the horrible reality, but it’s not here. This has been a wonderful environment."

"When he was eight years old, he was so small. I look back on the older episodes, I can’t believe how tiny these kids were and how we managed to get a show done," Molaro added.

But could Young Sheldon match or maybe even surpass Big Bang's 12-season run?

"That’s a bit above our pay grade actually," Lorre acknowledged. "[If] the audience is still enjoying the show and along with the journey then there's no question there’s a lot of stories to tell."

"I would love [to do] more," Armitage said. "I would be cool with whatever. I mean, we'll see. I don’t think I could tire of these people. We have some pretty wonderful castmates but hey, [seven] seasons is a lot but if we get to eight that would be incredible."

Young Sheldon airs Thursdays at 8 p.m. ET/PT on CBS.

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