How ‘The Big Bang Theory’ Cast Found out Johnny Galecki, Kaley Cuoco Were Dating

While filming The Big Bang Theory, stars Johnny Galecki and Kaley Cuoco did allude to their real life relationship. That is, once everybody else on the show found out. They kept their dating secret for as long as possible. Looking back after 15 years, they and their co-stars shared how they managed. 

Vanity Fair published an excerpt from Jessica Radloff’s 15th anniversary book on The Big Bang Theory. Cuoco, Galecki and others discussed their secret romance in the excerpt. The oral history book comes out Oct. 11.

Nobody on ‘The Big Bang Theory’ knew Kaley Cuoco and Johnny Galecki were dating

Galecki and Cuoco shared how their crush turned into an official relationship in the book. At first, Galecki wanted to keep their relationship private from the Big Bang Theory cast and crew.

“It’s not like we could make the excuse we were going to one of our rooms to rehearse because everyone knew I didn’t rehearse,” Cuoco said. “They wouldn’t believe that. They’d be like, ‘That doesn’t sound like Cuoco!’”

The Big Bang Theory creator Chuck Lorre was the first to find out.

“Chuck busted us hiding behind a car in the parking lot,” Galecki said. “It was after a show when we went outside, and we saw Chuck walk solo out of the stage. We were by some cars, and we ducked down, like kids hiding from their parents! And he totally busted us, but he was classy about it and didn’t say anything. We just didn’t want anybody to worry.”

Lorre claimed he can’t remember that. 

“That might be one of those things I compartmentalized like, I can’t deal with this, I don’t have the mental, emotional bandwidth to deal with an on-set romance,” Lorre said. 

The ‘Big Bang Theory’ crew caught Johnny Galecki and Kaley Cuoco too

Assistant director and director Nikki Lorre said another incident exposed Galecki and Cuoco. Galecki had missed a rehearsal and they ultimately had to go to his house to find him. It was Cuoco who knew the code to his gate. 

“I call Anthony [Rich] back at the studio, who hands the phone over to Kaley, and she tells me what the code is and how to get in,” Nikki said. “I remember thinking, How do you know all this, Kaley? [Laughs] But I had to bite my tongue.”

Kaley Cuoco wanted to tell the cast

Cuoco said Galecki’s initial concern was for The Big Bang Theory fans. He didn’t want them thinking of them together before Leonard and Penny became a couple. But, Cuoco convinced him to at least tell their co-stars. 

“We were in New York, and I said to Johnny, ‘I think we should tell the cast. It’s starting to feel like we’re lying to them,’” Cuoco said. “Johnny said, ‘I’m going to call Jim [Parsons] right now. I want to tell him.’ We call Jim on speaker, and Johnny says, ‘I’m in love with Kaley,’ or ‘I really want to be with Kaley,’ and Jim goes, ‘Ah! Does she know?!’ I started laughing and yelled, ‘Yes, I know! I’m here!’”

Cuoco and Galecki started socializing with Simon Helberg and his wife, Jocelyn, too.

“Johnny and I did a lot of things together with Simon and his wife, Jocelyn,” Cuoco said. “I think once they saw how much we liked each other and loved each other, everyone was into it. I’m sure they were probably more worried when we broke up, which was hard, yes, but it wasn’t some traumatic thing that we brought everyone into.”