Every actor has a process when it comes to learning their lines and performing their roles — and apparently, on The Big Bang Theory, Kaley Cuoco had a particularly interesting process. Specifically, her time as the series' original female lead Penny it was basically effortless, and it drove some of her co-stars and colleagues crazy (in the nicest possible way)—and she potentially came on set armed with a photographic memory.

Cuoco and her co-stars never specifically tell Jessica Radloff — who wrote the book in 2022.The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series— that Cuoco has an eidetic memory, but that's certainly implied by the fact that people who worked with Cuoco say she barely touched her script. As series creator Chuck Lorre said, “Caley would read cold and knock it. outside the park. He flew by the seat of his pants but never rested on his laurels. She was always working. She made it look easy, which is part of the genius. That's when you know there's a lot of work."

Former Warner Bros. president Peter Roth, who was incredibly involved with The Big Bang Theory and often spent time on set, agreed. "At every table read, I sat across from Jim (Parsons, played by Sheldon Cooper) and Kaylee," he recalls. "I remember going to Kayleigh and saying, 'When you get the scripts, you have to spend a lot of time re-reading them and highlighting them,' and she said, 'No, I've never read them.' I said, “Wait a minute, are you telling me these are cold readings?!” and she said, “Yeah, that's just something I do.” I swear, if you saw Kaley Cuoco at those readings, it was perfection, her timing was so flawless.

One can imagine that watching Kaley Cuoco effortlessly sail through dense, dialogue-heavy scenes on The Big Bang Theory was potentially frustrating, especially since her character didn't have to deliver scientific facts very often. Still, even when the writers tricked her into doing it, she pulled it off, according to her co-star, on-screen boyfriend-turned-husband and former real-life boyfriend Johnny Galecki (played by Leonard Hofstadter on the show). Galecki also stated their colleague Simon Helberg, played by Howard Wolowitzwas mystified by Cuoco's process.

"Wow, it was so boring," Galecki told Jessica Radloff. “I remember there was a speech the writers wrote as a dare for her that was at least a full page, if not more, and it was all physics jargon and she just nailed it. As Simon once said, she doesn't open a script for us, she just puts her hand on it and absorbs it by osmosis, and it's amazing."

Perhaps the craziest part of Galecki's recollection, though, is whatever was going on at Cuoco's house. "I would go to her house and walk through the gate, and there were three feet of scripts piled so high by the production assistants that they threw them over the gate," Galecki revealed. "And she never opened them!" I mean, months' valuable scripts lying in her yard. And yet she always knew her lines. I would study those lines so much. Whatever Kaylee's process is, or sometimes isn't, she knows exactly what will make things sparkle and pop, just by her own instincts. She is an anomaly."

As for Kaley Cuoco, the whole thing is pretty funny — which makes sense considering she apparently barely had to prepare for her scenes — though she also said Chuck Lorre is still suspicious about the whole thing. "Chuck still doesn't believe me when I tell him I didn't prepare for our table readings," Cuoco said in Jessica Radloff's book. "I even said to him once, 'I'm sorry, do you think after I shoot on Tuesday night, I go home and rehearse the script on Wednesday?' He says, 'Yeah, I think so?' I said, "Well, it's not like that, I hate to tell you!"

But in reality, Cuoco said she went through so many rehearsals as Penny that it was just easy to learn the dialogue — and that she really felt associated with her character. "The detailed version is that our scripts wouldn't change a ton from the time we got them to when we shot the episode, so we'd rehearse as the week went by and then we'd block on Monday, and it would just go into my memory from all of it," Cuoco said. “Also, I knew Penny so well, I knew what she was going to say before I read it.

The Big Bang Theory, including Cuoco's masterful performance as Penny, is now on Max.