More relationship problems will dominate the second episode of "The Big Bang Theory" season 9.

In the upcoming episode titled "The Separation Oscillation," Leonard (Johnny Galecki) will try to do everything to make it up to his new wife Penny (Kaley Cuoco) after their wedding night ended in disaster when she remembered that he kissed another woman while he was out on the North Sea. But can Leonard do anything to save his new marriage?

Meanwhile, Sheldon (Jim Parsons) will try to move on from the heartache caused by Amy (Mayim Bialik) after breaking up with him. Will this make Sheldon extra bitter this season?

The official synopsis of the upcoming episode reads:

"Leonard confronts the woman he kissed on the North Sea in an attempt to set Penny's mind at ease. Also, Sheldon films a special episode of "Fun with Flags" after his breakup with Amy, and Bernadette feels guilty about withholding a secret from Penny."

Based on the synopsis, Leonard will meet with the woman whom he shared a kiss with while in the middle of a North Pole exploration two years before he married Penny. This is to prove to his wife that there is nothing going on between them anymore. But will this move help save their marriage?

Meanwhile, the promo trailer for Monday night's episode shows a clip of the latest "Fun with Flags" webisode, where Shelton publicly declares that "all the things my girlfriend used to do can be taken care of with my right hand." Amy is actually watching the episode, which naturally infuriates her. Things seem to be getting worse between the former lovers in "The Big Bang Theory" season 9.

In other news, Bernadette's (Melissa Rauch) guilt about keeping a secret from Penny will consume her during the upcoming episode. Will she finally confess her secret despite knowing that Penny is already dealing with a big problem with her marriage?

"The Big Bang Theory" season 9 episode 2 airs tonight, Sept. 28, on CBS.