In the next episode of the "The Big Bang Theory," Penny Hofstadter (Kaley Cuoco) befriends her husband, Leonard's (Johnny Galecki) mom, Dr. Beverly. However, Leonard does not want them to become close friends.

The trailer for the upcoming installment titled "The Explosion Implosion" was just released which showed Beverly talking on the phone to Penny who seems surprised to be getting a call from her. Penny and her mother-in-law do not actually have anything in common and do not communicate much. However, it seems like Beverly wants to get to know Penny because she does not have any friends.

Leonard, on the other hand, does not want Penny and his mom to get close or become friends because he still resents her for not giving him enough attention when he was younger. "Do you not want me to be friends with your mom?" Penny asks Leonard. Apparently, she and Beverly have been talking a lot more lately to the dismay of Leonard. He replies, "Let's be clear. I married you to hurt her."

It implies that Beverly did not approve of Penny which is why Leonard married her to spite his mom. Now, however, Penny and Beverly becoming friends would make things awkward for Leonard. It remains to be seen what will become of their new family dynamic.

In the last episode, Sheldon Cooper (Jim Parsons) had a hard time picking out a wedding date because he wanted it to be perfect and conformed to all of his quirky requirements. He felt so stressed out after mulling over it for many days that he finally allowed his fiancée Amy Fowler (Mayim Bialik) to plan the whole celebration.

It is expected that they will be married in an upcoming episode this season.

"The Big Bang Theory" season 11 episode 4 will air on Monday, Oct. 16 at 8 p.m. EDT on CBS.