Amy, Bernadette and Penny will attempt to recreate a moment from their past in the next all-new episode of "The Big Bang Theory."

In the last episode, "The Expedition Approximation," Sheldon's new work in dark matter led him into an underground adventure into the university's steam tunnels with Raj. The two faced tough conditions, including over 100 degree heat, humidity, dynamite explosions and rats. Fortunately for fans, the plotline allowed viewers to see the two characters interact and share great scene chemistry as they cracked jokes about Star Trek Voyager, miners' songs, and Miley Cyrus, reports Entertainment Weekly.

In the meantime, Leonard and Penny faced challenges in their relationship after Penny decided to sell the car that Leonard bought her now that she has a new company car. Leonard insisted that Penny should keep the cash that she got in exchange for her old car since the car was a gift. However, Penny turned it down and accused her fiance of being upset because she no longer needs his financial support. In turn, Leonard told her that she has control issues.

Eventually the couple turns to Howard and Bernadette for relationship advice, which doesn't work out well.

By the end of the episode, Leonard says he would be okay if Penny makes more money because the emasculation of men in marriages is part of a loving relationship.

According to a new promo video, "The Big Bang Theory" will no longer air on Mondays. Instead, it will broadcast on Thursday nights, starting with Season 8, Episode 7, which will premiere on Oct. 30.

Hollywood Hills reports that the upcoming episode is titled "The Prom Equivalency" and its synopsis reads as follows: "Amy, Bernadette, and Penny will end up, trying to re-enact their high school proms with their respective fellows. Raj, Emily, and Stuart will be included too."

"The Big Bang Theory" Season 8, Episode 7, "The Prom Equivalency" will air on Thursday, Oct. 30, at 8 p.m. ET on CBS.

Watch a teaser clip below.