Relationship drama will continue to be a central theme when Season 9 of "The Big Bang Theory" debuts in the fall.

The Season 8 finale ended with an emotional cliffhanger as Sheldon and Amy's slow-moving relationship came to a dramatic end. After dating for years, Amy told Sheldon that she was fed up and frustrated with the lack of growth in their relationship and needed space.

Meanwhile, Leonard and Penny decided to elope in Las Vegas, but Leonard had second thoughts and nearly sabotaged their relationship.

"They're still driving to Vegas but the mood is certainly a little chilly," teased showrunner Steve Molaro during an interview with The Hollywood Reporter. "They're in a very interesting place and we'll find out what happens when they get there," he said.

In addition, Molaro hinted that other members in the geeky gang will also experience relationship troubles next season. 

Although Raj has made a lot of progress in communicating with women, Molaro said that he will still find the task daunting.

"Just because he can do it doesn't make him good at it," said the EP.

Molaro added that Raj will also face a dilemma over whether or not he should break up with Emily.

"He's in interesting position for a guy like this. For the most part, when you're lonely, it's easy to have feelings for a person because they like you back. Raj is starting to wrestle with the thought of, maybe that's not the ideally the best situation for him. That's a tough thing for a guy like Raj, to think, 'Wow, am I going to end a relationship and be by myself when I could be with this person who likes me and wants to sleep with me?' It's a big, mature thing to wrap your head around for a character that spent so much time being lonely for so long," he said.

He continued saying that the two are still together, but that their relationship is not perfect. And some things are very hard to come back from, such as Raj not being fully OK with who Emily is as a person. 

"His next hurdle is how to navigate this relationship and see if he has this strength in him to do what's right for him -- even if it means being alone. How uncomfortable is he willing to be to not be alone?" Molero added. 

Furthermore, Howard and Bernadette will face new hurdles over living in his mother's home. 

"This is tough; this is a house that he grew up in with his mom -- who he was very attached to -- and [that] he and Bernadette are trying to make this 'their' home when it feels like his mom's home is an interesting thing. That's one thing that they'll probably be trying to deal with," Molero said.