'The Big Bang Theory' season 10 news: Jack McBrayer teases return; Penny-Leonard wedding sparks relationship rumors

In the premiere episode of the "Big Bang Theory" season 10, viewers finally met Susan (Katey Sagal), Penny's (Kaley Cuoco) mother, and Randall (Jack McBrayer), her older brother.

Randall, who has been referred to numerous times in the past, had just been released from prison, allowing him to attend Penny's wedding with the rest of their family. In previous episodes, it was revealed that Randall was "a kind of chemist" and worked in a meth lab.

The character was played by "The Big Bang Theory" guest star McBrayer, who is best known for his Emmy-nominated role as Kenneth Parcell in "30 Rock." While the season 10 pilot marked McBrayer's debut on "The Big Bang Theory," it might not be the last time fans see him on the sitcom.

In a recent interview with Yahoo! TV, the actor spoke about his guesting, saying, "It was so fun, and they were very straightforward from the beginning."

As for whether or not he will be returning to Pasadena sometime in the future, he said, "I knew going in, just make my appearance and be a good guest and maybe later on down the line Randall can come back to visit. They were such gracious hosts, I would like to be a gracious guest."

Meanwhile, the wedding of Penny and Leonard (Johnny Galecki) in the season 10 premiere made fans wonder if Cuoco and Galecki, who are real-life exes, have rekindled their romance.

The "Big Bang Theory" co-stars reportedly broke up in December 2009 after about two years of dating. Their real-life romantic relationship coincided with their characters' romance on the sitcom.

Since ending their relationship, Cuoco and Galecki have reportedly remained good friends. In September 2013, Cuoco married tennis star Ryan Sweeting. Their divorce was finalized in May this year.

But while "Big Bang Theory" fans may love the idea of the real-life Penny and Leonard getting back together, it sounds like the two are happy just being friends.

Earlier this year, Cuoco addressed the rumors that she and her co-star have started dating again, telling Cosmopolitan earlier this year, "Johnny and I are very close now, but the worst part about that is I don't want stories like that, especially during this divorce, to hurt my ex."

"The Big Bang Theory" season 10 airs Mondays at 8 p.m. EDT on CBS. It returns to its regular scheduled day after the National Football League coverage on Thursdays starting Oct. 27.