Sheldon (Jim Parsons) and Amy (Mayim Bialik) will face a big conflict in their new living situation, which might put the whole experiment to a halt. Meanwhile, Bernadette (Melissa Rauch) will be adjusting to big changes when her baby comes.

Previously in "The Big Bang Theory," a busted pipe in Amy's apartment soaks everything inside and leaves her room flooded. Penny (Kaley Cuoco) suggests that Amy move in with Sheldon. Sheldon is doubtful of Penny's proposal, but after a few persuasive scientific arguments from Amy and Leonard (Johnny Galecki), Sheldon decides to proceed with their "experiment" of living together with Amy in Penny's apartment.

In episode 5 — titled "The Hot Tub Contamination" — Sheldon and Amy will be having a huge fight about Sheldon's bathroom rules. According to the synopsis released by Spoiler TV: "Leonard and Penny must separate a quarreling Sheldon and Amy when their cohabitation does not go as planned, and Sheldon threatens to break off their relationship when Amy refuses to adhere to the bathroom schedule."

In the trailer for episode 5, Amy is seen reasoning with Sheldon about what is "normal" for bathrooms, but Sheldon refuses to accept and threatens that they should "see other people." Could this be the last straw for Sheldon and the end of the couple ever living together?

However, based on the episode title "The Hot Tub Contamination," it could be an indication that Amy will win over Sheldon in their bathroom argument and ultimately asks for a compromise that she will follow Sheldon's rules if they bathe together in the tub.

This season will also focus on the progress of Howard (Simon Helberg) and Bernadette's marriage, and how pregnancy has affected Bernie.

In an interview with Glamour, showrunner Steve Molaro hints that there will be a lot of changes in Bernadette's life when the baby is born. "Bernadette has pretty publicly said that she doesn't really like kids and didn't really want them, so we've had an opportunity to dig in a very honest and interesting way when you find yourself in that position. Her career is going great, and this is not necessarily something she was striving for, but it's happening," Molaro explained.

It appears that Bernadette will be changing her priorities soon once the baby comes, and that she will be going through a few emotional roller coasters while adapting to those changes.

"The Big Bang Theory" season 10 airs every Monday at 8 p.m. EDT on CBS.