[WARNING: The following story contains spoilers about Thursday's episode of The Big Bang Theory. Read at your own risk.]

The universe started with a big bang, and Sheldon and Amy ended the year with one.

Shamy finally did the deed on Thursday's The Big Bang Theory after Sheldon (Jim Parsons) was faced with his Sophie's Choice: see Star Wars: The Force Awakens or have sex with Amy (Mayim Bialik). But his choice wasn't sex at first. After deciding to see the movie on opening night instead of spending Amy's birthday with her, Professor Proton (Bob Newhart) visits Sheldon in his dream as his Obi-Wan to encourage him to be with Amy instead to show how important she is to him. And so Sheldon comes up with three gift ideas on his own before consulting with Penny (Kaley Cuoco) and Bernadette (Melissa Rauch): have Amy play the harp with the L.A. Philharmonic, go on an all-expense paid trip (just her, not him) to the Wisconsin Sheep and Wool Festival or have "coitus with her."

"I'd like to show her how important she is and it feels like now might be the right time," he says when the girls ask him if he's sure about the latter. "Then it's settled. Amy's birthday present will be my genitals."

Even though the girls spill the beans to Amy, that does little to dampen her excitement or nerves, and after a short and sweet exchange, they at last consummate their relationship. The whole thing is not shown onscreen, but is more than worth the wait for Amy (less so for Sheldon) and fans who've watched how much they've both grown over the years. Also worth the wait? The Force Awakens, which the guys see in another arc of buildup, anticipation and ultimately pure ecstasy.

So what's next for Shamy after their own big bang? Executive producer Steve Molaro answers our burning questions below.

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When you broke up Amy and Sheldon, had you already decided that they would have sex when they got back together?
Steve Molaro:
It's been something that's been floating around obviously in the air for years. We knew it was going to happen someday and it seemed to be the perfect little bow on their arc of this season that began at the end of last season when Amy broke up with him. When the idea started to gel that it could be so neatly tied into the Star Wars movie premiere, that's when we really started to get excited about it. We knew that the movie was going to start being shown the night this episode was going to air. We just got more and more excited about it. And also I had known in the back of my mind for a while that it would be amazing if Bob Newhart could come back in his ghostly Jedi form to help Sheldon navigate this moment with a moment in a way a father might with his son.

So we can thank Star Wars is what you're saying.
Molaro:
Always! [Laughs] The planets just started to align there.

Did you consider them not having sex or was this was the logical next step they needed to take?
Molaro:
Either one was a completely legitimate way to go, but I think Amy's been waiting, you could say, five and a half years. That might be enough time. ... We started thinking about it a few years ago. It was sort of floating quietly in the back of our minds. It was just figuring out when was the right time to do it.

What was it like writing the episode?
Molaro:
Exciting, fun, terrifying, pressure-filled. Just like it was for them! [Laughs] We love all these characters and we knew this was a big moment for them and the show, so we were just trying hard to get a version right that we could hopefully all feel good about.

This is obviously something big and monumental, but you didn't overdo it in the episode and all their actions and reactions felt very true to the characters.
Molaro:
I hope so. That was our goal. In general, when the characters have some sort of personal growth — and all seven of them clearly have had them over the years — when the episode's done, they still feel like the characters. We try so that it's not such a shift that it doesn't even feel like that character anymore. That's something we do keep in mind quite a bit, especially when we do big episodes like this.

Sheldon came up with them having sex on his own. How important was it for it to be his idea rather than him coming around to it if it were suggested by Professor Proton or Amy?
Molaro:
Right. [Professor Proton] said, "Just be with her, show her how important she is to you." I think it made it more interesting. And it was nice that while Professor Proton had a hand in it, Sheldon came to the thought on his own. It didn't come strictly from an outside character. I think that was really important. It shows how much he's changed. It's slow, but it does happen. He's thinking of Amy and considering her feelings. She's been dragging him a lot of the way over these last few years. I don't think you'd want to see an episode like this where you feel like he might be getting forced to do something that he might not really have his heart in.

I don't know if people expect Sheldon to be super nervous, but I like that he wasn't. As he said, he knows the mechanics, so he was more practical about it and he hasn't built it up in his mind like Amy has.
Molaro:
Yeah, I think that's a good word. Sheldon's very practical. I think the heart of that scene to me, for all the talk about it for all these years, is that Amy is nervous, I think rightfully so. I think in that situation, and for that character, that's exactly what would happen. And I thought they both played it so beautifully. Even though this big milestone in their relationship happens, it really is more about all that goes into it and getting there and why they're finally ready.

The parallel excitement and nerves over Star Wars was great. Was it easier or harder to write that knowing that the A story was?
Molaro:
We were aware that one story was so monumental that we wanted to find a way to have the other story balance that out. I think with the global excitement of the Star Wars movie premiere certainly helped make that happen. It's just so geeky and silly how they were acting, but it makes sense too. This is just as big [as sex] for a lot of people. Hopefully we meshed the two of them together in an interesting way.

I love the implication that Sheldon and Amy lasted as long as the movie did.
Molaro:
[Laughs] Uh-huh! Me too! Everybody spent about two hours in bliss.

What's next for Sheldon and Amy? They made two big steps in the past two episodes with their make-up make-out session and now this. Is he really going to make her wait a whole year to have sex again?
Molaro:
[Laughs] I don't think it'll be a year. I think it's time to take a little bit of a step back. The entire season so far has been pretty Sheldon-Amy-centric following their breakup and reuniting. This gives us a chance to take a little breather. Obviously, they're in it and they matter, but it's a chance to let them be happy in the background and refocus on the other amazing characters on this show. I don't think they will change too much from this. It's not something that's going to be harped on to death. They're back together and it's going well.

Will the engagement ring pop up again?
Molaro:
At some point, I'm sure it will. I promise you we have not forgotten about it.

Since you did something for Star Wars, are you going to do something for Star Trek Beyond? That comes out in July, so you can't sync it up exactly.
Molaro:
Not yet, but you know we are equal opportunity with Star Wars and Star Trek here. We are big fans of both franchises. We did do a pretty big Star Trek episode last month with the Spock documentary and we had Leonard Nimoy's son on the show, so Star Trek has been represented this season if we don't do anything later.

What did you think of the episode?

The Big Bang Theory airs Thursdays at 8/7c on CBS.

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