Amy & Sheldon's Big Relationship Milestone Led To The Big Bang Theory's Best Episode

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There are a lot of huge, important moments on "The Big Bang Theory" and almost as many great episodes of the series created by Chuck Lorre and Bill Prady, which ran on CBS for 12 years and the same number of seasons. Still, ask any fan and they'll probably tell you that season 9, episode 11, "The Opening Night Excitation," is one of the very best chapters of "The Big Bang Theory" ... because it's the one where Sheldon Cooper (Jim Parsons) and his longtime girlfriend Amy Farrah Fowler (Mayim Bialik) finally consummate their relationship.

Okay, that sounded weird. Let's back up! Sheldon, in his original form, was potentially supposed to be asexual, so it's a big deal that the series even gave him a love interest. Amy, though, is the perfect match for Sheldon — a brilliant and socially awkward neuroscientist who's just as exacting and specific as he is — and after agonizing about what to get Amy for her birthday in the episode, Sheldon realizes what he needs to do. Even though "Star Wars: Episode VII — The Force Awakens" is set to hit theaters on Amy's birthday, he skips the movie and has what he terms "coitus" with his girlfriend for the very first time, and from then on, it's a yearly event.

In Jessica Radloff's 2022 book "The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series," multiple people dished on making this episode — and why it turned out so well. As executive producer and writer Steve Molaro explained, "It was such a delicate thing to have Sheldon and Amy finally have sex. I had been sitting on them sleeping together being an 'annual event' for years. It would either be Valentine's Day or her birthday, and obviously we decided on her birthday. We're all so protective of them as a couple and as characters, so there was this immense pressure to get the moment as good as we thought it could be. And then when you actually start putting the plan into motion, it's scary. Especially something like that. Most people have been through that experience for the first time and it's scary. It's intense and surreal and weird, so why pretend it wouldn't be?"

"For the longest time, they never wanted to make Sheldon a sexual being, and now that they were crossing that bridge ... it was not that it was jumping the shark, but it felt like it had that potential," Chuck Lorre's daughter Nikki Lorre, who wrote and directed multiple episodes of "The Big Bang Theory," shared. "Like, if we don't do this right and treat it with the utmost respect, then we could really put people off. There was this excited energy, but also wanting to make sure not to taint a very beloved couple. [But] the audience just lost their minds. I was very impressed with how they handled that."

Executive producer Steve Holland knew that "coitus" between Amy and Sheldon was all but inevitable ... but he was genuinely worried the characters could change. "Their relationship took off on its own from the moment they met, and it was so much fun to write for," Holland explained. "But even though you want to show their growth, you're also worried about what part of the show you can't break and have it still feel like 'The Big Bang Theory.' We wanted to make sure Sheldon wasn't suddenly going to be a lothario or feel like a different person in a weird way." For her part, Mayim Bialik expressed a similar sentiment, pointing out that Sheldon and Amy's relationship was different than anything else on television:

"I would have been happy for their relationship to never be sexual, and instead just be a romantic, intimate love. I didn't know if we were ready for it. And I think it was really neat to have a nonsexual committed relationship on a sitcom. So, Jim and I were both surprised that the writers were ready to take it to this level. But also in hindsight, I still believe that our writers are correct."

Ultimately, after Sheldon and Amy went through a brief split in the story (and, obviously, got back together), both Bialik and Jim Parsons were completely caught off guard when they realized what was coming (pun absolutely intended). "We found out the big moment was happening the night before we did the table read," Bialik told Jessica Radloff. "I always wait until the next morning right before we sit down at the table, but this time I started reading, and I passed Jim in the hallway and said, 'Did you read the script yet?!' He said 'No. Do we do it?' and I said, 'Yes!' He was like, 'What?!' He just threw it out there as a joke. We couldn't believe it."

"It was really insane," Parsons agreed. "One of the great things from my experience at least, was that I never knew what was coming. When Mayim said that we 'do it,' I went, 'Oh! Oh my God.' I mean, it was a wild guess! It was absurdist to think that's what would happen."

Okay, so a few other questions. Why does Sheldon use the word "coitus" to describe the sex he has with Amy (before and after the act) instead of using a word that's less ... blunt? If you have to ask yourself that, you don't know Sheldon Cooper very well. As Chuck Lorre explained, "'Coitus' was a clinical word that seemed appropriate for Sheldon, because he wouldn't use slang. Having Sheldon speak technically about sex felt appropriate. It's a biological expression, as far as he is concerned. But not anymore because he had an emotional experience with Amy. It's a huge growth for the character."

Because this represents a big emotional leap for Sheldon, Steve Holland realized the show needed a sort of role reversal between Sheldon and Amy ... in that Sheldon needed to be the calm, rational person about such a big step. "Which is why before the episode happened, [Steve Molaro] thought that whenever they do sleep together, Amy should get super nervous beforehand, and Sheldon has to be the calm one who talks her through it," Holland remarked.

Makes sense, but why "Star Wars?" Well, "The Opening Night Excitation" did air on December 17, 2015 ... and "The Force Awakens," the first film in the sequel trilogy (mostly) helmed by J.J. Abrams, came out literally one day later in the real world. Still, even if the timeline hadn't worked out quite this beautifully, "Star Wars," like Amy, is one of Sheldon's great loves, so forcing him to choose between the two — and him choosing Amy in the end — just felt perfect.

"I'm a huge 'Star Wars' fan, so I had the thought that 'The Force Awakens' could be the thing that Sheldon could give up for Amy's birthday," Holland explained. "It wasn't even about the coitus. It was just as a gift to Amy, he could skip the 'Star Wars' premiere and spend her birthday with her, which seemed like a really sweet thing. And because it was her birthday, that meant we could say it would be an annual event that we could do once a year. That way Sheldon was still pretty much Sheldon."

"The Opening Night Excitation" turned out perfectly, and it's all because the crew behind "The Big Bang Theory" helped their characters beautifully through a new, unexplored milestone. You can watch this episode, along with the whole series, on HBO Max now.