The Big Bang Theory boss on that shocking hookup

Warning: This story contains major spoilers from the season finale of The Big Bang Theory. Read at your own risk!

Penny and Leonard planned to renew their wedding vows in The Big Bang Theory finale — though they didn’t quite make it down the aisle.

It turns out, the CBS comedy went for a soft cliffhanger surrounding the arrival of Leonard’s (Johnny Galecki) father Alfred (Judd Hirsch), who we learn has a terrible relationship with ex-wife Beverly (Christine Baranski). Because of that, Alfred found common ground in hating Beverly with Sheldon’s (Jim Parsons) mother Mary (Laurie Metcalf), which leads to what one can only assume is a steamy hookup considering they’re both MIA the next morning. Alas, we won’t know until the fall, which is why EW turned to executive producer Steve Molaro to get the scoop:

ENTERTAINMENT WEEKLY: Presumably, Alfred and Mary hooked up, right?

STEVE MOLARO: I don’t know what happened. I know they were getting along quite well, and left to go to the same hotel for a nightcap, and turned off their phones. The details of exactly what happened, if we even ever find out all the details, will be left for the season premiere of season 10.

How will Sheldon and Leonard react to that? This is potential for them to actually be brothers.

It’s inching toward that, isn’t it? There was — it fell out of the script — a joke referring to them as potential brothers. I’m going to go with the word “uncomfortable” probably is a good starting place for their primary emotion of where we leave them and where we will pick up.

What came with the decision to do a cliffhanger unrelated to the main cast?

We tend to end seasons on a bit of a cliffhanger, so that’s nothing new there. We had known for a while that we wanted to meet Leonard’s father. Judd and Johnny had met and hit it off. Judd had expressed interest, so we were all excited about that. That had been floating around in the mix and it seemed like a fun story, and I think a very interesting stopping place for the season.

Does that mean that next season will pick up right where you left off?

There’s nothing set in stone, but for now that seems to be the plan.

With Penny (Kaley Cuoco) and Leonard slated to renew their vows, will that make Amy (Mayim Bialik) and Sheldon think about the next step, like moving in together?

Maybe, possibly. It’s so soon. Those two move famously glacially, so one microscopic baby step at a time for them.

As you’re moving these couples forward, are you having discussions about actually having Leonard and Penny move in together without a joint custody of Sheldon?

There are no rules in place. Obviously the show does continue to evolve and grow, but at the same time, there’s a basic DNA that’s built into it. I don’t think we’re in any rush to break that DNA. If and when it feels natural, it could happen, but for now, for me, Leonard-Sheldon-Penny floating around in those two apartments is a pretty important basic building block of what The Big Bang Theory is. At this point in time, we’re not rushing to people moving out.

You’ve taken some big steps with a number of the couples — Amy and Sheldon had sex, Bernadette (Melisaa Rauch) and Wolowitz (Simon Helberg) are expecting a baby. How do you think that changes the tone of the show moving forward? And how nervous are you about taking these couples to the next step?

You could call it nervous, you could call it excited. It’s probably a good thing, any nerves about this, that means we’re making changes that matter. Ultimately that growth is exciting and good for the health of the show. The goal is to make those kind of changes and sure, Wolowitz and Bernadette pregnant, that’s a big step, but it’s also a manageable one. I don’t think it sets the show on fire or is a tremendous change. They have a support system in place. If we want to have an episode with a baby in it, if we want Bernadette’s parents or Stuart watching the baby and we just want to do an episode about Wolowitz that has nothing to do with babies, that’s still completely doable. It expands our little universe without breaking it in any way.

Will next season delve much deeper into baby planning?

Sure. We’ll continue to look for new takes on that and the kind of stories that hopefully we haven’t seen many times on TV. So far, I think we’ve done a pretty good job with that in season 9. The pregnancy will continue.

Are you looking at season 10 as the final season?

No. Right now, on this show, we go one episode at a time. I’m not really thinking of it that way. Twenty four episodes is so many episodes that that’s not a thing we’re thinking about right now.

Have you thought about how you would like to see the show end?

I have personal thoughts that have been floating around in my head, but we haven’t really talked about it. It always seems like this thing that’s off in the distance forever. Until it becomes closer to a reality, I’m not going to think about it all that much, because it makes me sad.

When you took the reins on the show, were there benchmarks that you wanted to make sure you hit before the eventual end of the show?

No. In anybody’s life, there are these tentpole events of weddings, babies and deaths. These characters are humans just like anybody else. I don’t think there’s a checklist, but there are obvious life events pretty much for all of them that you could imagine. When they feel right, we do them. If the time isn’t right, we would never force it. It’s not like there’s some list getting checked off of Bernadette must be pregnant by end of season 9. That couldn’t be further away from what it really was, which was a spur of the moment thought in the middle of writing the episode.

As you head into a tenth season, what makes you nervous about keeping up the standard that Big Bang Theory fans expect of the show?

Sure, it’s a thing that can be daunting at times. We have the luxury of a group of incredible writers, and a group of insanely talented actors. As long as we start excited and keep pushing forward, a little bit of that nervousness is crucial to the process.

For you personally, what’s one thing you’re excited to explore next year?

I’m excited for all of it. I’m excited to meet more family members, I’m excited to start to meet Penny’s family, I’m excited to see what’s going to happen with the baby, I’m excited about what the Air Force wants with the [guys]. There’s a lot of fun balls in the air right now.

The Big Bang Theory is expected to return in the fall on CBS.