The Cohabitation Experimentation Season 10, Episode 4 -  Aired October 10, 2016

The Cohabitation Experimentation

After Amy's apartment is flooded, Penny suggests that Amy move into Apartment 4A with Sheldon. Unsure about finally cohabiting with his girlfriend, Sheldon comes around to the idea when he looks at it as a five week experiment in living together. Sheldon suggests they move into Penny's old place, Apartment 4B, so they would know if he's comfortable because he's living with Amy and not just comfortable in his own apartment.

Meanwhile, Howard and Bernadette decide not to learn the gender of their baby, but they question their decision when Raj reveals that he knows the sex of the baby.

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Writers: Chuck Lorre (Story), Dave Goetsch (Story), Maria Ferrari (Story), Steven Molaro (Teleplay), Steve Holland (Teleplay), Tara Hernandez (Teleplay)

Director: Mark Cendrowski

Viewers: 14.41 million Households Rating: 9.1/14 Adults 18-49 Rating: 3.4/12

Available on iTunes

Episode Lists

  • Sheldon & Amy: Key Episodes Sheldon & Amy: Key Episodes

    The key moments in Sheldon & Amy's relationship including Howard & Raj setting them up, the signing of the relationship agreement, the first time they said "I love you", them breaking up and subsequently getting back together, the proposal, the wedding and winning the Nobel Prize together.

Episode Notes

  • The title refers to Sheldon and Amy's decision to try living together after her apartment was flooded.

> Sheldon's Spot

When Penny promises Sheldon that they won't sit in his spot if he moves into her old apartment, Sheldon says that "no  matter where I am, this will always be my spot. Like an embassy in a foreign country, this seat is the sovereign soil of my bottom."

> Sheldon's Knock

While considering whether to move across the hall into Penny's old apartment and making it his "official residence", Sheldon wonders whether he would need to knock when he comes back to Apartment 4A.

When Sheldon does come back to Apartment 4A after spending the night in 4B, he doesn't knock on the door but does end up repeating the phrase "I didn’t knock, but it's fine" three times.

Episode Quotes

Penny: We wouldn't even sit in your spot while you're gone.
Sheldon: You're darn right, you wouldn't. No matter where I am, this will always be my spot. Like an embassy in a foreign country, this seat is the sovereign soil of my bottom.

Penny: Do they know why the pipes burst?
Amy: They didn't say.
Leonard: Buildings that have a combination of copper and galvanized steel are susceptible to pinholes and corrosion caused by the mobility of ions in the water. Can't have your head shoved in a toilet as much as I did and not pick up a few things about plumbing.

Penny: The new neighbors are weird.

Leonard: Never leave a belt on the floor. At night, they look like snakes.

Amy: Listen, you and I are gonna be sharing a bed. You know, this is uncharted territory for both of us. How are you feeling about that?
Sheldon: Oh, excited, concerned, a little scared. All the same emotions I feel in line at Space Mountain.

News Stories

Title Date Posted
1004 'The Cohabitation Experimentation' Press Release September 30, 2016

CBS has issued the press release for the fourth episode of The Big Bang Theory's new season, "The Cohabitation Experimentation", which airs Monday, October 10.  Full story


When Leonard, Penny and Amy arrive at the apartment building with food, Amy tells Leonard and Penny that her apartment flooded and she’ll be out of the building for five weeks. Penny offers Amy a place to crash, saying she can stay in Leonard’s old room and they’ll stay in Penny’s apartment instead. Amy is excited to think she’ll be moving in with her boyfriend, while Leonard and Penny are thrilled with the idea they might finally live as a married couple without Sheldon. When they get to the apartment, Sheldon wonders why they’re all smiling “like crazy people.” 

In the apartment, Leonard and Amy are unpacking the food, while Sheldon explains his discomfort having to deal with a change in his living situation. Amy appeals to the scientist in him by describing it as a five-week experiment. Leonard suggests that Sheldon think about it like a Star Trek mission. Sheldon is still unsure because he wouldn’t know whether he’s comfortable because he’s living with Amy or because he’s in his own apartment. Penny suggests her apartment as a neutral place. After Sheldon thinks it through, he accepts Amy’s invitation to live together in Apartment 4B. 

In Howard and Bernadette’s kitchen, Raj says he is happy with their OBGYN, though Howard and Bernadette are not sure why Raj keeps attending their appointments with them. After Bernadette wonders if they are being silly not finding out the sex of the baby, Raj confesses that he looked at their folder at the OBGYN and knows the gender of their baby. Although Raj says it’s not a problem because he doesn’t have to tell them, they’re still upset that he knows and they don’t.

Back at the apartment building, Sheldon goes to Penny’s apartment to ask her for advice about living with one’s significant other. Meanwhile, Amy seeks similar advice from Leonard. Later, Sheldon is packing up his bedroom when Amy asks if he is coping well with the change in living situation. When Amy suggests they talk through the sleeping arrangements, she offers to take being physical off the table for now if it would make Sheldon more comfortable. 

Sheldon, Amy, Leonard and Penny gather in the hallway to swap keys and say goodbye. As soon as Sheldon and Amy get into their new apartment, they hear Leonard & Penny celebrate their new freedom in the hallway. In their new bedroom, Sheldon asks Amy which side of the bed she would prefer. Amy would prefer Sheldon to just make a decision since he cares more about those sorts of things than she does. She gets worked up when Sheldon struggles to come to a decision.

Over at Howard and Bernadette’s, Howard gets ready to join Bernadette in bed. She is worked up about all the people who know the sex of their baby when they don’t. After Bernadette stands to wonder if they’ve made the wrong decision in not knowing, Howard suggests it might better to be surprised - like a magic trick. Meanwhile, back in Sheldon & Amy’s bedroom, Sheldon is uncomfortable listening as Amy goes to the bathroom before bed. When Amy gets into bed, she asks Sheldon how he would feel about other forms of intimacy, like snuggling. Sheldon was going to suggest building a pillow wall between them, but Amy thinks she’s made more than enough concessions for him.

Meanwhile, Leonard and Penny are happy when he points out it’s past Sheldon’s bedtime so they’ve definitely got the apartment to themselves for the night. They are happy to be alone, but they struggle to know what to do with their new freedom. Leonard wants them to dance in their underwear, after which sex would be inevitable. Elsewhere, Howard and Bernadette decide to find out the sex of the baby so they phone up Raj. When Bernadette instantly changes her mind, Howard hangs up. 

Back in Sheldon and Amy’s bedroom, Sheldon is thrashing about and talking in his dream, irritating Amy. Meanwhile, Leonard and Penny are dancing around in their underpants. Elsewhere, Bernadette says she is positive she wants to know the sex of the baby, so Howard rings Raj again.  Bernadette once again changes her mind. 

Amy struggles to sleep as Sheldon keeps making noises. Amy tries closing Sheldon’s mouth, but it doesn’t help. Meanwhile, Leonard is using his inhaler - Penny did warn him against doing the worm. Elsewhere, Raj gets another phone call, only to overhear Bernadette saying she changed her mind again. 

Amy is finally getting comfortable snuggling with Sheldon, until he starts thrashing about and knocks her out of the bed and onto the floor. When Amy’s fall wakes Sheldon up, she reaches for her phone to get some light. After Amy accidentally uses her phone’s camera, the flash frightens Sheldon and sends him scampering out of the room.

The next morning, a tired Amy gets a cup of coffee from Penny over in Apartment 4A. Leonard is sore from dancing the night away. Amy admits to Penny that she’s not sure she will make it five weeks living with Sheldon. When a refreshed Sheldon enters, Amy tells him she doesn’t think she’ll be able to keep living with him. Sheldon says they would be bad scientists if they drew a conclusion after just twelve hours of data. After Sheldon and Amy argue about their scientific integrity, they agree to continue their experiment for science.