TV URBAN LEGEND: A major “Big Bang Theory” plot twist wasn't originally planned for the episode in which it was revealed.

Television writers and producers have to be willing and able to adjust their plans at the last moment because of all sorts of unforeseen situations. For example, “Ally McBeal” had to write Robert Downey Jr. out of his own wedding episode, and “Alias Smith and Jones” had to come up with a way to keep the show going after one of its stars killed himself. Those were outside influences, though.

Sometimes series also have to adjust when the writers end up going in a wildly different direction than they’d originally intended. That was the case this season with the hit sitcom “The Big Bang Theory,” which revealed a major plot twist the writers didn’t even have in mind when they began work on the episode in which it was revealed.

In this season’s Valentine's Day-themed episode, "The Valentino Submergence," married couple Howard (Simon Helberg) and Bernadette (Melissa Rauch) plan on having a romantic night in their hot tub. When they open it up, however, they find a rabbit floating in it. As it turns out, the rabbit wasn’t actually dead yet, and they nurse the animal back to health. In the process, it bites Howard, who heads to the emergency room for a rabies shot. Left behind with the rabbit, Bernadette says, "We'll find another time to tell him I'm pregnant."

It’s a shocking revelation, especially as Bernadette had previously expressed no desire to have children any time soon.

As it turns out, the episode was completely planned out and outlined without the dramatic revelation! It was only the night before taping that plans abruptly changed. As showrunner Steve Molaro explained to The Hollywood Reporter:

We've touched on the idea of Bernadette and Howard and children here and there but we didn't really have plans to pull the trigger at any point. It wasn't even part of the outline for the episode. We were writing it and getting toward the end of the story and I guess maternity was in the air because Bernadette was holding this wrapped-up bunny and they named it, and we were writing the final page of that storyline. Half-kidding, I said, "What if Bernadette tells the rabbit, 'We'll find another time to tell him I'm pregnant'?" The room had such a strong, positive reaction to it. We thought it seemed like an organic moment and we decided to put it in. Because there was no plan for it, it felt very exciting to us when we did it; like it was a thing that should happen and maybe this was the time to do it.

He told Entertainment Tonight that he then handed show creator Chuck Lorre the script right before the episode was to be filmed:

"I handed the script over to Chuck the next morning and I said to him, 'I tried a couple things. See what you think,'" Molaro explained. "He had no idea and he came back later with the script and he goes: 'So, Bernadette is pregnant? Sure, why not? Go do it!' and he walked out and that was that."

The news came as a surprise to the rest of the cast as well. Some took it better than others, as Entertainment Tonight learned from star Kaley Cuoco:

When we asked Kaley Cuoco if she's excited to be working with some potential twins on the Big Bang set, the blonde beauty was completely unfiltered with her response: "No, I'm not," she said bluntly. "Maybe [Bernadette] can be pregnant for, like, three seasons so we can wait a couple of years, but we'll see," she said.

"No dogs and no babies -- that's my rule," Cuoco added. "At home, yeah, but not on set. Not at work."

You have to at least somewhat admire the adventurous nature of the show's writing. A last-minute addition was also the origin of how the word "Bazinga" was added to the "Big Bang Theory" lexicon, but adding a word to a script and adding a whole pregnancy are entirely different things!

The legend is...

STATUS: True

Thanks to Leanne Aguilera of ET and Lesley Goldberg of The Hollywood Reporter for the information! And, of course, Steve Molaro and Kaley Cuoco.

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