"The Big Bang Theory" returns to CBS this Thursday, Jan. 9 with an all-new episode in which Leonard will have to deal with the repercussions of turning down Penny's marriage proposal.

Last week, the couple hit a rough patch after an emotionally distressed Penny proposed to Leonard and he replied by saying "ummm." In the upcoming episode, titled "The Occupation Recalibration," Leonard will spark a conversation with Penny about the kind of relationship that they are in.

This season's upcoming epsidoe will also focus on Sheldon who is forced to cope with temporary joblessness.

TV Line revealed that Bernadette's pursuit to replace one of Howard's prized geek zines takes her to Stuart's comic-book-store competition, which happens to be an awesome establishment and a riveting displaying of everything that Stuart's comic book store isn't. One of the photo stills from the episode show that the eye-catching shop is tricked out with all the latest graphic novels, action figures, collectible statues and limited edition lithographs.

According to Hypable, a couple of guest stars will appear in the show including Josh Peck of Nickelodeon's "Drake & Josh," who will play Jesse, the owner of a comic book store that rivals Stuart's glum shop. In the meantime, Ian Scott Rudolph will return as comic book store regular Captain Sweatpants, however he will turn heads in the unusual setting of Amy's laboratory.

The official synopsis for "The Occupation Reconfiguration" reads:

"Sheldon tries to relax after he is forced to take a vacation. Meanwhile, Leonard struggles to be supportive of Penny after she quits her job, and Bernadette seeks Stuart's help in replacing one of Howard's comic books."

"The Big Bang Theory" season 7, episode 13, "The Occupation Recalibration," will air on Thursday, Jan. 9 at 8:00 p.m. on CBS.

Check out a preview below.