Big Bang Theory

Of all the possible Big Bang Theory couplings, do any of them make for stranger bedfellows than Raj and Penny?

"I really don't think so! Especially if my reaction means anything," executive producer Steve Molaro tells TVGuide.com. "I remember Chuck [Lorre], Bill [Prady] and I were in the writers' room breaking the season finale and that story of [Raj and Penny sleeping together] came up. I think I had a strong reaction to it — facially. I was like, 'Really?!' I think Chuck was so amused by how strong my reaction was that he was like, 'Well, now we have to do it!'"

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And of course they did it — and so did Raj (Kunal Nayyar) and Penny (Kaley Cuoco), who were caught red-handed doing the Walk of Shame after their drunken one-night stand and tried to issue the classic "It's not what it looks like." The Season 5 premiere picks up shortly after the revelation and finds everyone still reeling from the turn of events — especially Penny's ex, Leonard (Johnny Galecki). But to hear Molaro tell it, the hookup may just be karma for Leonard.

"Leonard is with [Raj's] sister! What goes around comes around. It's karma. He wants to be irritated by it, wasn't he just sleeping with Priya in Raj's bed?" Molaro says. "He's not in the best place to have much of an argument. But Leonard is in a tricky spot. While this is a weird situation for him to process, on paper, he has a girlfriend, and Penny and Raj are adults. Really, how much does he have to say about this? At the time same, he could be quite rude about it. I think that's why it's such a neat situation. We're all human and I can certainly understand why he's weirded-out. I think everyone is."

The weirdness, however, won't be dragged out, as there will be a resolution to the "little mess" by the episode's end and will see all the relevant parties scatter off. Penny will still be single, while Leonard will try his hand at a long-distance relationship with an India-bound Priya (Aarti Mann) that's "really going to test them." But don't think that means Penny and Leonard will reconnect. "In the way they got together and the way they broke up, which was not part of any grand plan, I don't know what's going to happen," Molaro says. "We just sort of take each week as it feels. If it feels at some point something should stir between them, then we'll go with it. But I'll say there will always be lingering feelings between Penny, Leonard and Raj."

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And Raj? Well, he'll take the biggest step of all when, in the third episode, Penny — yes, Penny — hooks him up with a potential girlfriend with whom he can finally communicate without the help of alcohol. That's because Emily (Katie LeClerc) is deaf. "[Raj and Penny sleeping together] not only is a big deal for the show, but it's a big deal for him," Molaro says. "This is a guy who can't speak to girls and he's not a completely different person after this who can easily hit on girls, but he's not the same one either. So we'll see him kind of navigate that. And it's about time he got some lovin'!"

Indeed, Raj has been the only one of the four guys without a female companion. Sheldon (Jim Parsons) and Amy (Mayim Bialik) will continue their odd yet perfect relationship ("It is a relationship, just not a sexual one," Molaro describes), while Howard (Simon Helberg) and Bernadette (Melissa Rauch) will move forward with their wedding plans. Echoing showrunner Prady's statements from earlier this summer, Molaro says they still have not decided if the couple will tie the knot by the end of the season.

"As of now, the plan is someday they will," he says. "They're, like a real couple, making plans right now and we're right there with them. They will continue to discover things about each other that maybe they should've talked about before they got engaged. And you've got Howard's mom to deal with too, which I don't think any bride wants to! She will be around in the first three episodes. The relationship between Bernadette and Howard's mom and the way the three of them interact will continue to grow. We know she likes Bernadette, so that's already a good start. We'll see how the planning goes."

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And do those wedding plans include bachelor and bachelorette parties? "Not yet, but I will not be surprised if that occurs," Molaro says. "I would imagine that is something Amy, especially, would be very interested in. I'm assuming that she's never been to one and this is her chance."

It would also give Raj a chance to mingle with the ladies. "Raj at a bachelor party! That would be something," Molaro says. "Maybe by then he won't be so [dependent] on alcohol to talk to girls. It has become a crutch for him. I cannot even imagine what he'd be like at one!"

The Big Bang Theory premieres Thursday at 8/7c on CBS.