'The Big Bang Theory' Tell-All: Kaley Cuoco Nearly Had to Amputate Her Leg and More On-Set Secrets (Exclusive)

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AsThe Big Bang Theory celebrates its 15th anniversary, a new tell-all book is peeling back the curtain on never-before-heard stories and revelations from the hit CBS comedy's 12-season run. 

The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series, available now, chronicles the behind-the-scenes tales you may not have known to bring the popular sitcom to life -- from the initial casting process to the show's breakout success to the real-life, off-set circumstances that threatened to derail the series. 

Series creator Chuck Lorre and author Jessica Radloff sat down with ET's Nischelle Turner to dig into the most illuminating revelations from the book, which features new interviews with the cast and producers, and go down memory lane of what almost did or didn't happen.

"There’s a general sense of gratitude that we got to take this journey and 12 years is an incredibly long time to do one thing and there was a genuine affection amongst everyone," Lorre shared. "It was difficult to end it."

While Lorre opted not to get into the legacy of the show yet, he acknowledged that Big Bang Theory has made a lasting impact.

"The fact is, we made a show that we were very fortunate that actually, people cared about it. They cared about the characters. They saw that they saw themselves," he said. "They saw alienation because these are characters who struggled to move in this world, but made a community amongst themselves. And that was the life raft, that they created their own life raft and that was something to aspire to. They ate together; due to budgetary reasons, initially, probably. But ultimately, they always ate together. And those scenes were what a family does. We ate together, we met each other, we loved one another and we made each other miserable. That's what a family does."

Here are the biggest takeaways from The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series.

1. Johnny Galecki Turned Down the Role of Leonard Multiple Times

In the book, it's revealed that Galecki said "no" to the part of Leonard Hofstadter several times before someone on his team persuaded him to take another look. Lorre admitted that casting Galecki, who had starred in the '90s sitcom, Roseanne, was a roller coaster. "I didn't keep track but yeah, it was a bumpy ride," he recalled. 

"What’s so interesting too about Jim [Parsons] is that Jim had the hardest role in terms of the dialogue and everything else and yet you can agree he was the easiest person to cast, it was instantaneous," Radloff said, offering context. "Johnny turned it down five times in a row. He said that you and [executive producer] Bill [Prady] were sending fax pages to him because he was in New York doing a play and he was just getting pages here and there, it wasn’t a complete script. He wasn't sure and it really took a lot of convincing from his agent, who said, 'Just go out and do the pilot.' It was [his] agent after a while that convinced him."

2. They Completely Reimagined the Main Female Character, Which Led Them to Kaley Cuoco

Lorre recalled audiences were not connecting with the original female character they had proposed in the initial version of The Big Bang Theory, with actresses like Elizabeth Berkley, Marisa Tomei and Tara Reid being bandied about. In the original draft, the main female character was almost the antithesis to Penny.

"When we started we didn't know that the audience was going to feel protective of these brilliant characters because they're almost childlike," he said of the central group of Leonard, Sheldon, Howard and Raj. "They're incredibly intelligent, mind-bogglingly smart men who were extremely vulnerable and the audience just couldn’t tolerate any kind of hostile character around them. The original character, I think, was called Katie. We had created a character who was in trouble, who was trouble coming."

"The actress, Amanda Walsh, did an incredibly great job. She did exactly what was asked of her, but the audience didn't want that character near these guys," Lorre reflected. "So, when we got a chance to do it again, we shifted the character and changed the name to Penny and made her very warm and tolerant of them. And in a way, she became the conduit for the audience because she was us. 'What are you guys talking about? What planet have you come from?' She was the surrogate audience."

Because they were starting from scratch, Lorre confessed there wasn't much to Penny's backstory to begin with and her presence helped inform the show's focus. "We didn't develop the character of Penny terribly much initially. That came later," he said. "We did make the mistake in the pilot... of the ditzy, pretty girl and that’s a cliche. We ran from that and decided the show is ultimately about intelligence and how far does intelligence get you in this world. And there’s different kinds of intelligence. There’s academic intelligence, there's common sense and Penny represented common sense. She had people skills, she understood how to move through this world. She had no idea what their world was, but they couldn't do what she could do and she couldn't do what they can do. But they complemented one another."

Lorre praised Cuoco, who earlier in the day revealed she was pregnant with her first child. "She’s just genuinely a big-hearted, warm and wonderful and incredibly skilled actress and congratulations having a baby!" he said.

3. Simon Helberg Didn't Know Kevin Sussman Was Originally Cast as Howard 

Helberg, who played Howard Wolowitz for 12 seasons, actually wasn't the first and only actor cast in the role. As the book reveals, it was Kevin Sussman, who'd later recur as comic book store owner Stuart Bloom, who initially had the role for a brief period of time. As Radloff shared, Helberg had no idea until the making of this book.

"I remember talking to executive producer and showrunner Steve Molaro. I said, 'Steve, Simon was wondering. There was about a week period between auditions where he didn't hear anything and he's like, I felt like something was going on. When I talked to Kevin Sussman, Kevin told me that he actually had the role of Wolowitz first. My jaw was on the floor. I wanted to know why have you never said anything?'" she said. "That shows what an amazing guy Kevin Sussman is. He never wanted to get in Simon's head and to make him think you weren’t the first person cast, which was so incredible to do that. Very, very kind."

"I will never forget that phone call with Simon one day when I had to tell him that he was not originally the first person cast as Wolowitz and that was really hard," Radloff continued. "I was freaking out so much that he had to come comfort me. He said, 'I have goosebumps all over. This completely tracks with what I thought might have been going on, but to hear something that you thought you knew for 15 years...,' and that’s where he says, 'I knew we would learn things in this book, but wow, I did not expect this to be it.'" 

"There were so many bumps in the road along the way making of this show," Lorre said, adding that Sussman couldn't do the show because of a contractual obligation he had to ABC's Ugly Betty, which he was co-starring in at the time. "At the very last minute, ABC or someone there decided they wanted him back and he never came back [to Big Bang Theory]. That’s what was so hard about it, that he never did come back."

4. Chuck Lorre Was the Last to Know About Kaley Cuoco and Johnny Galecki's Real-Life Romance

Cuoco and Galecki began dating early on in the Big Bang Theory's run, splitting up in 2009. Lorre said there were concerns over how a breakup could affect the show and its storylines.

"At the time I thought, 'Well, if they break up, how do we go forward with them as a maybe romantic pair on-camera? Maybe it’s a bad breakup, it's completely out of control?' You're in the backseat of the car, you're not driving and so yeah, I was certainly concerned," he shared. "I think we were are at Comic-Con, we were in the shuttle bus [and] I’m sitting next to Kaley and I’m trying to have a conversation. 'So what’s going on? You seeing anybody? What’s going on with you?' And she goes, 'Oh my god, you don't know.' And I'm going, 'I don't know what?' Everyone else knew, I was the last to find out."

Any concerns he and the producers had about a breakup potentially making things difficult on set ended up being a moot point, as Cuoco and Galecki have maintained a strong friendship since ending things romantically. "They did break up and they handled it. They became the best of friends, and very loving and supportive of one another. It was never even a tiny hiccup," he credited. "They were brilliant in their humanity towards one another and how they transitioned from romantic relationship to a platonic relationship, and it was great. Never missed a beat, it was never a concern."

5. Kaley Cuoco's Horseback Riding Accident Was More Serious Than Previously Thought (and She Nearly Lost Her Leg)

In 2010, Cuoco was in a terrifying horseback riding accident in Los Angeles that was far more serious than the public knew. In the book, the actress recalls details of that fateful day when the horse she was riding got spooked and bucked her off, running over her and landing on her left leg. 

"It was very serious and Kaley still has a really hard time talking about it," Radloff said. "When we were doing the interview,  she was saying Johnny was getting very emotional. Johnny would cry during these conversations and Kaley was like, 'We don't have to go there, we don't have to go there,' and it was important for Johnny to talk about because he says it really showed us how vulnerable we are. How important we are to one another. Thank god Kaley came out of this OK. The reason she came out of it OK is because of Chuck. Chuck helped get her the care at Cedars-Sinai that she needed and... when she was in recovery, he would come and play his guitar for her and bought her a rocking horse and said, 'This is the only horse you're now allowed to ride.'"

"Yeah, she didn't listen to me. She got back on the horse," Lorre quipped. "She became like family, it wasn’t just a business relationship." Lorre said Cuoco's injury was "devastating." "There were so many things that happened that had they not happened, she might've lost the leg," he noted.

Miraculously, Cuoco only missed one episode. "We made her a bartender instead of a waitress, so she was behind the bar. She stood behind couches, or she was seated, and we made it as easy as possible, and I think during the whole course of that fiasco she missed one episode, which was a miracle," Lorre said. Radloff added that in an episode after the accident, Cuoco had to run back into Penny's room. "It’s the one time she had a stunt double. Kaley talks about it [in the book]. She's like, 'You can kind of tell but that is not me running back into my room because I wasn’t able to do it.' A fun little Easter egg."

6. Jim Parsons Wanted to End 'Big Bang Theory' After Season 12

Lorre and Radloff recounted how the cast reacted when Parsons expressed a desire to leave The Big Bang Theory after the end of the 12th season, which ended up being the series' farewell year. "As best as we could," Lorre said. "At the time I certainly I couldn't imagine continuing the show had anybody wanted to leave. It’s just the ensemble was this perfect gem and to take any part of it away would've been -- something would be missing and I just couldn't imagine doing a show without Sheldon. You'd always be aware of that [hole], that vacuum, that empty space would always be there and it would've made it very difficult to carry on."

"We had a meeting with everybody -- all the actors -- and Jim explained to everyone that he wanted to end the show at the end of the 12th season," he continued. "And it was really tough because no one saw it coming and it was an emotional time for a long time, but looking back, because we did it early, we had an opportunity to really think about how to end the series and I'm proud of the way we ended the series."

Added Radloff, "The thing that I learned about the very last season and especially that first meeting when Jim did say that he was ready to go is that there was no right way to do this because how do you say goodbye? I think everybody truly handled that situation the best way they knew how to with the information that they had, and I thought that talking to them all now you understand where each person was coming from, and I also don't think Jim Parsons gets enough credit for playing the role of Sheldon Cooper for 12 years."

With the benefit of hindsight, Lorre shared that the cast believes they ended the show at the right time. "Oh yes, absolutely. In hindsight, we're so glad we landed the plane the way we did. It wasn’t about money or prestige or anything like that, it was about art. [Jim] wanted to do other things as an actor. How can you not support that?"

The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Stores is available now.


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