Kaley Cuoco remembers the 'dark' character she almost played in original version of 'The Big Bang Theory' (exclusive)

When The Big Bang Theory aired its series finale in May, Kaley Cuoco bid farewell to Penny, a role she had played for 12 seasons and almost 300 episodes. But in one of the parallel universes that her neighbors and science nerds Sheldon and Leonard (Jim Parsons and Johnny Galecki) might have dreamed up, Penny wouldn’t exist at all. In a new featurette included on The Big Bang Theory: The Complete Series box set that’s hitting shelves Nov. 12, Cuoco and the show’s co-creator Chuck Lorre reveal that the version of Penny we know and love wasn’t in the show’s original pilot. “I had actually auditioned for the original pilot, and I did not get cast,” the actress says. (Watch the video above.)

To be clear, Cuoco didn’t audition for Penny in that initial pilot, because Penny didn’t exist yet. Instead, she tried out for the role of Katie, who Lorre describes in the featurette as “a dark, brooding unhappy woman.” (The part eventually went to Amanda Walsh.) Lorre also admits that there’s a good reason why no one has ever seen the original Big Bang pilot. “[It] was just a mess. Not because of the actors, but because we didn’t really understand the characters yet. We had to go through that failure to understand that if a woman was going to be in [Leonard and Sheldon’s] ecosystem, she had to be gentle with them because they were really vulnerable.”

So Lorre and his writers started over from scratch, replacing Katie — and another female character, Gilda (Iris Bahr) — with the more “maternal” Penny. Once the character existed on the page, he called in Cuoco to bring her to life onscreen. “Chuck called a year later and said, ‘It’s a new character, we want you to come in,” she remembers. “I read for it and it just felt so much better than it did the year before. I guess it was just meant to be.”

The Big Bang Theory: The Complete Series will be available to purchase on Amazon, Target and Walmart on Nov. 12.

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