The Big Bang Theory EP Describes Penny's Family

The upcoming 10th season of CBS's The Big Bang Theory will start things off with a great deal of focus on Penny's family, a unit that fans have heard a great deal about but have hardly seen on screen.

That will change when Actress Katey Sagal (Sons of Anarchy) joins the show as Penny's mother Susan and Jack McBrayer (30 Rock) takes the role of Penny's brother Randall. They will join her father Wyatt (Keith Carradine), who has previously been featured on the show.

Executive Producer Steve Molaro recently described the family dynamic that fans will get a glimpse of in the series opener. While we don't know if they'll be returning later in the season, they are certainly planning on leaving a big impression during the premiere (via EW).

"Penny's close with her dad. As we know, her brother Randall has been a bit of trouble over the years, selling drugs and being in and out of jail, and that's put a lot of stress on her mom. You will pick up on the tensions between her mother and her brother very quickly, and you get a glimpse of Penny and her dad being caught in the middle of that."

Randall has been referred to throughout the series, most recently as of last season during The Convergence-Convergence episode. There it is revealed that he's been released from prison thanks to overcrowding.

This will be a reunion of sorts for Sagal and Cuoco, as the two also starred together in 8 Simple Rules. As for Penny, Molaro has previously said her career will also be a subject for the show this season.

"We believe in the world of 'The Big Bang Theory' that the movie she did with Wil Wheaton, Serial Apetist, is floating around and developed a cult following. One way Penny could make money is signing autographs for fans."

The Big Bang Theory returns on September 19th at 8 PM ET on CBS.