The Explosion Implosion Season 11, Episode 4 -  Aired October 16, 2017

The Explosion Implosion

When Howard worries about raising another child, he and Sheldon bond as they assemble a model rocket together. Meanwhile, Leonard is freaked out when he learns that Penny and his mother have become friends.

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Guest Stars: Christine Baranski as Beverly Hofstadter, Dana L. Wilson as Dr. Samuels, Michael Patrick McGill as Police Officer

Writers: Bill Prady (Story), Maria Ferrari (Story), Tara Hernandez (Story), Steve Holland (Teleplay), Eric Kaplan (Teleplay), Jeremy Howe (Teleplay)

Director: Mark Cendrowski

Viewers: 13.07 million Households Rating: 8.6/14 Adults 18-49 Rating: 2.8/11

Available on iTunes

Episode Notes

  • The title refers to Sheldon and Howard's failed attempt to launch a model rocket.

Episode Quotes

Bernadette: What about this?
Raj: Uh, okay. Uh, pull off the skirt, slap a lightning bolt on the front, and you got baby Flash. Ooh, stick a long sleeve under it. Boom, Baby Sheldon!

Sheldon: You're a good teacher. Your son is going to be lucky to have you as a father.

Leonard: Come on. You can build things. You were an astronaut.
Howard: That's true. You know, as a kid, I used to make model rockets. That'd be pretty cool to do with a son.
Sheldon: Model rockets. Finally, something interesting! What is your preferred mode of recovery?
Amy: Sheldon, we're helping our friends.
Sheldon: And we got to model rockets, yeah? It was a tedious road, but well worth the effort.
Amy: So, have you thought of any names?
Sheldon: Amy, we finally got to model rockets. Why are you turning back?

Penny: What's up?
Beverly Hofstadter: Well, I enjoyed our conversation the other day, and I was hoping to continue it.
Penny: Really?
Beverly Hofstadter: Uh, yes. You may find this surprising, but I don't have a lot of what you would call girlfriends.
Penny: (exaggerated) What?
Beverly Hofstadter: Of course, there are my female colleagues, but, uh, they're all Freudians, so the only boy that I can dish about is my father. (chuckles)

Howard: You don't even have a license.
Sheldon: Actually, I do.
Howard: Really? Since when?
Sheldon: Three years ago. I went on a bit of a license kick. I'm also a commercial fisherman.

News Stories

Title Date Posted
1104 'The Explosion Implosion' Press Release October 9, 2017

CBS has issued the press release for next week's episode of The Big Bang Theory, "The Explosion Implosion". Christine Baranski returns as Leonard's mother, Beverly, in the episode.  Full story


As Howard and Bernadette wait in the OB/GYN’s office ahead of a prenatal scan, Howard remarks that it doesn’t feel long ago that they were doing this for Halley. As Bernadette points out, that’s because it wasn’t, so she jokes they should get Howard a vasectomy before they go. When they are asked if they want to know the sex of the baby, they say they do want to know and don’t have any preference for a boy or a girl. When they are told they’re expecting a boy, they are deflated.

When Bernadette and Howard join the rest of the gang over dinner in the apartment,  everybody is trying to cheer them up about the prospect of raising a boy. When Howard admits he would like somebody he could build model rockets with, Sheldon is finally interested in the conversation. When Amy tries to change the topic, Sheldon is unhappy.

As Leonard gets ready to leave the apartment, Penny wonders where he’s going. He explains he’s going back to the dry cleaner because they failed to get the stain out of his Starfleet uniform. Just before Leonard goes, the laptop sounds to indicate an incoming video call from Beverly. Leonard rushes out, saying she just missed him, so Penny takes the call. When Penny asks Beverly how she’s been, she talks about her personal life including intimate details of her latest dalliance.

When Sheldon and Raj join Howard in his garage to look through his old model rockets. Sheldon finds a model Saturn V that Howard’s dad got him. When Howard says it’s silly how he never opened it because his dad abandoned them, Sheldon disagrees and says he always wished his dad had been interested in building rockets with him. Despite his anger towards his father, Howard feels building this stuff was what led him to being an engineer. Howard suggests he and Sheldon build the rocket together.

Inside the house, Raj explains to Bernadette why he didn’t want to hang out with Sheldon and Howard. As Bernadette sorts through clothes that Halley has outgrown, Raj shows a remarkable knack for knowing how to turn the girl clothing into something suitable for a boy. Meanwhile, Howard is driving Sheldon into the desert so they can launch the rocket. When Howard mentions a NASA tradition of having peanuts on hand for every rocket launch,  Sheldon thinks it’s a superstition. When Howard counters that it’s more of a tradition, Sheldon is disappointed they don’t have any peanuts with them. As Sheldon obsesses about getting peanuts, Howard tells him it may just be a superstition after all.

Penny is going to grab a drink from the refrigerator when she gets a phone call from Beverly. Penny is surprised when Beverly says she was calling for her, not Leonard, because she enjoyed their conversation the other day. Beverly explains that she doesn’t have many girl friends and, since they talked about her last time, they should talk about Penny’s life. After Penny points out that real girlfriends would gossip about a third party, Beverly tries to be catty by calling Amy “dour”.

Out in the desert, Howard runs back from the rocket as Sheldon’s gets ready to film the lift off. After Howard’s countdown causes an argument with Sheldon, the rocket just blows up. Howard is disappointed that the one thing he thought he could do with his son, he can’t even do right.

In the apartment, Penny is making a sandwich for Leonard and is annoyed when he texts her from the couch asking for more mustard. Penny threatens to throw out the sandwich when she gets another text, but this time it’s from Beverly. Leonard is surprised that his mother is texting her. Penny admits that she’s been talking to Beverly a lot lately and says that Beverly’s been supportive of her. When Penny tells Leonard that Beverly said she is proud of her, Leonard is upset that his mother has never said that about him.

As Sheldon and Howard clear up the doomed rocket, Sheldon gives Howard reasons to feel good, but Howard is unmoved. Elsewhere, Raj is using a sewing machine in Bernadette’s living room to change one of Halley’s old clothes to fit a boy. When Raj asks Bernadette if she’s upset about having a boy, Bernadette says she’s fine but after growing up with a bunch of brothers, she had hoped that Halley would have a sister.

Leonard goes over to Amy’s apartment to tell her he’s freaking out about Penny being pally with his mother. Amy is more bothered by the fact her “bestie” has a new friend. Leonard and Amy both get worked up, but they’re talking across each other. After Amy thinks she hasn’t been spending enough time with Penny lately, Leonard leaves after declaring “Good talk.” Meanwhile, Howard is still freaking out as he drives Sheldon home from the desert. When Sheldon asks if he can drive, Howard says no as he doesn’t have a license. After Sheldon tells Howard he actually does and has for three years, Howard eventually agrees to let Sheldon take the wheel.

When Leonard starts a video chat with his mother, Beverly is disappointed when she answers and finds it’s not Penny. After Leonard asks her why she isn’t proud of him but feels able to tell Penny she’s proud of her. Beverly admits that Penny is the favorite of all her children’s spouses, and she is proud of Leonard for marrying well.

As Howard coaches Sheldon as he drives them back from the desert, Sheldon tells him his son will be lucky to have him as a father. When Sheldon wants to drive a little faster, Howard agrees but Sheldon speeds up way too much. Later, when a cop pulls them over, Sheldon seems pleased to declare they were going 112 miles per hour. After handing his driver’s license to the cop, Sheldon tells him he can keep it.