Just to give this a bit of perspective, The Big Bang Theory — the hit sitcom that celebrates all things nerdy and has proven that the geek shall inherit the Earth (if they haven't already) — is currently 254 episodes into what is so far an 11 season run. But at the time that Kaley Cuoco, Penny herself, sat down with me to talk about the show (10 years ago in 2008, when she was 22 years old), only eight episodes had aired. Despite that, the series had already begun connecting with the audience, and made stars of Jim Parsons (Sheldon Cooper), Johnny Galecki (Leonard Hofstadter, the actor already an audience favorite thanks to his role as David Haley on Roseanne), Simon Helberg (Howard Wolowitz), Kunal Nayyar (Raj Koothrappali), and, of course, Kaley (who had already scored TV hits with 8 Simple Rules… for Dating My Teenage Daughter and Charmed).

kaley cuoco- big bang theory cast

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The sense that I got from her is that she was having a great time, already recognizing that they had something special there, and this was in the days before the cast grew to include Melissa Rauch (Bernadette Rostenkowski-Wolowitz), Mayim Bialik (Amy Farrah Fowler), and Kevin Sussman (Stuart Bloom). "I've never been so excited about a show before," she laughed. "In fact, last night I had the whole cast over with our significant others and we watched the show together. It was so cute; we had such a good time." Which made me wonder if they'd all bonded really tightly at that point. "Well, the guys are really close. I know Simon, Jim, and Johnny hang out a lot, and I'm kind of like their annoying little sister that follows them around and wants to hang out, too. But they're way too cool for me. We've all definitely formed a very strange relationship, all five of us. It's so quirky and nuts."

kaley cuoco - cast and producers

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And it almost didn't happen at all. The original pilot shot for The Big Bang Theory had a different actress in the role of Penny. Cast was actress Amanda Walsh instead. While that Penny still moved in across the hall from Leonard and Sheldon, she was a less attractive character in personality and came across kind of mean in the way she treated the guys. A negative example of her character was the proud claim she had slept with her stepfather before her mother got married to him. Okaaaaay. CBS turned down the pilot, but liked the premise enough to commission another one from series creators Chuck Lorre and Bill Prady.

kaley cuoco - penny and sheldon

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Things obviously worked out okay as far as Kaley was concerned, a point driven home when she let out a squeal of excitement when asked about her character. "I love Penny, and I think she's crazy, too," she said. "They all think they're normal in a certain sense, but they're all so screwed up and so odd. That's what I love about it. Penny, she's definitely the standing tree amongst the crazies. She's kind of like the little mother bear. I feel that way on set, too, with all my little cubs…. You may not have noticed it, but I'm really enamored with this cast. Now that we get the sense that we're going to be together for a while, we've really gotten attached to each other."

While Kaley really enjoyed scenes involving the five main cast members at that time, there was absolutely something special about those moments between Penny and Sheldon. "When Jim and I have our scenes, they're just priceless," she enthuses. "He is such a genius, and I don't know how he does the look he does. Actually, I do. He's like that all the time, which makes it even funnier. It's not too far off. He just cracks me up."

kaley cuoco - penny and leonard

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So, in those early days, just what did she feel was the appeal of the series? "To have a hit show," Kaley offered, "you have to have characters that are lovable. These guys are so lovable, and they're charming and they're non-offensive and they're not in your face. And my character is not this raging sexpot who women don't want to watch and men are bothered by. She's not obnoxious. I think people are falling in love with Leonard and Sheldon, and a lot of these characters, and they want them to do well. They want Leonard to get the girl in the end."

Which, of course, he eventually did, with Leonard and Penny gradually falling in love and then getting married. But even at that early stage, she believed that Penny had feelings for him. "Obviously they're very opposite," she explained, "but I think she has an attraction for him because he is so different. And the thing about Penny is that she's non-judgmental, and it doesn't bother her that these guys are so weird. She loves them anyway."

kaley cuoco - sheldon and leonard

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A humorous moment occurred in the conversation when I asked her what she tended to geek out about — an appropriate question given the nature of The Big Bang Theory — to which she excitedly replied, "Johnny actually answers it like this: when you immerse yourself into something, like you go crazy about something and get kind of geeky, whether it's at a football game waving a big foam finger…."

I interrupted her with a laugh, because literally the day before I'd spoken to Johnny Galecki and used that exact analogy in our discussion. Kaley laughed, "Oh my God, he was just telling me that last night. We were talking about you!"

Aw, shucks, Kaley.

kaley cuoco - horseback

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Then, wrapping things up by answering the question about her personal geekiness, she added, "I am a total Western horse geek girl! I have horses. I spend my days I'm not working at the ranch cleaning up horse manure, and feeding the horses, and I immerse myself in that world. I'd rather be there than anywhere else. I could stay there till the sun goes down; in fact, that's where I'm going right after we're finished here. I just love it. I ride every horse that's out there, and just enjoy it so much. So I think that's kind of geeky. There's not a lot of people I share this experience with, but it's definitely my thing."

The season finale of The Big Bang Theory airs Thursday, May 10.