Ending The Big Bang Theory was difficult for the cast, especially for Kaley Cuoco and Johnny Galecki, who took the news to heart. Meanwhile, Jim Parsons and the rest of the team felt a sense of relief and freedom after starring in the series for 12 seasons.
Concluding the show was not an easy choice, though not having the slightest idea of what was to happen was even more frustrating. The reactions of the show's members varied, and some of them took the situation very gravely.
Kaley Cuoco portrayed Penelope 'Penny' Hofstadter in The Big Bang Theory, and the bad news came as a shock to her, especially after appearing in 12 seasons. At first, the actress could not grasp what Jim Parsons was talking about, but after finally moving on from the denial stage, she broke down and cried. Cuoco told BuzzFeed:
"The shock of 'Oh my god, what is next?' was scary. I mean, we cried for hours that day. We thought we were going to do another year, so all of the sudden your life kind of flashes before your eyes. I couldn't breathe. It just felt like a death, but also a new horizon for everybody as well."
Because of the terrible news, Cuoco almost did not go to work. It caused a lot of trouble and delays in the filming. Showrunner Steve Molaro revealed:
"I got a text that morning from Kaley saying she didn't know if she could work that day because she was still really upset. Upset with Jim. The first run-through back was kind of icy and none of them were talking between scenes, but everyone was professional."
After they talked everything out, the actors went back to the set and finished the final season. Although the tension was still there, they were skilful enough to conceal it.
Another cast confirming how Jim Parsons betrayed all of them was Johnny Galecki. Like Cuoco, the actor confessed he was unprepared for the bad news. He wished that it was handled more maturely:
"I was shocked. We were just blindsided that day. And not necessarily shocked by Jim's decision, but that he hadn't had that conversation with his cast mates first to prepare us. So yes, it could have been handled better. We're a family; have a conversation."
The news took a toll on everyone, and Galecki almost wanted to question the decision to wrap up the series. But, seeing everyone was disheartened, the actor just tried to be understanding.
On the night of their taping for the final episode, Kaley Cuoco shared that she and Galecki stood on the stage crying while the entire room listened to their speech (via Variety):
"Johnny and I just stood there, and we were crying. I looked down, and the whole stage, all the crew, had all filled the stage to come up next to us while we were talking. They were just listening to us like we were the last speech they were ever going to hear."
Though it was difficult to accept and it gave her bouts of depression, Cuoco admits The Big Bang Theory was a "once in a lifetime experience." She praised her co-stars and professed her deep affection for each of them.