The Colonization Application Season 8, Episode 17 -  Aired March 5, 2015

The Colonization Application

As Sheldon and Amy take a step forward in their relationship and choose to buy a pet turtle, Amy is angered to learn that Sheldon has applied for a one-way mission to colonize Mars without discussing it with her.

Meanwhile, Leonard and Penny take a step forward in the bedroom when Leonard makes an adult purchase, while Raj worries about Emily's reaction when she finds out he's been snooping in her apartment.

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Guest Stars: Laura Spencer as Emily

Writers: Dave Goetsch (Story), Jim Reynolds (Story), Tara Hernandez (Story), Steven Molaro (Teleplay), Eric Kaplan (Teleplay), Maria Ferrari (Teleplay)

Director: Mark Cendrowski

Available on iTunes

Episode Notes

  • The title refers to Sheldon's application to join a one-way mission to colonize Mars.

Episode Quotes

Penny: This is why I've been saying we should keep champagne on ice.
Sheldon: Sarcasm?
Amy: Yes.
Sheldon: That was tricky because when it comes to alcohol, she generally means business.

Sheldon: I'm exceedingly smart. I graduated college at fourteen. While my brother was getting an STD, I was getting a Ph.D. Penicillin can't take this away.

Howard: How are the taxes going?
Bernadette: Okay, but you've got a lot of receipts for the Lego store in here.
Howard: Those are business expenses. You can write those off.
Bernadette: A $200 R2-D2 is a business expense?
Howard: Oh, Bernie, you're gonna have to sound a lot more confident when we get audited.

Bernadette: What's happening?
Howard: Raj was snooping through Emily's drawers and broke one.
Bernadette: Oh, I'm gonna miss her.

Leonard: We cover ourselves in body paint and then we get on this big canvas and do our thing.
Penny: Woah, that's kind of a big step for a guy who only recently agreed to take his socks off.

News Stories

Title Date Posted
817 'The Colonization Application' Ratings March 6, 2015

Last night's episode of The Big Bang Theory posted week-to-week gains to finish as Thursday's most-watched and highest-rated show.  Full story

817 'The Colonization Application' Pictures March 3, 2015

Pictures from the next episode of The Big Bang Theory, "The Colonization Application", have been added to our gallery. In the episode, Amy is angered to find out Sheldon has applied to be part of a one-way mission to colonize Mars. Penny is surprised when Leonard buys an "adult" gift, while Raj worries how Emily will react when she finds him snooping in her apartment.  Full story

817 'The Colonization Application' Press Release February 26, 2015

CBS has issued the press release for next week's episode of The Big Bang Theory, "The Colonization Application". Laura Spencer returns as Emily, Raj's girlfriend.  Full story


As Leonard and Penny return to the apartment building after a session of Mini Golf, Leonard is extremely proud of his game, even though Penny won. When they return to the apartment, Sheldon and Amy tell them about the big decision they've made in their relationship: they're getting a pet turtle. Elsewhere, Emily tells Raj her roommate is away so he can finally stay over in her apartment. When Emily is called in to the hospital to check on a patient, she tells Raj to stay in her apartment.

At a pet store, Sheldon and Amy go to pick out a turtle. As Amy tells their prospective pet how he'll be living with Sheldon, except when he's at Comic-Con or on a work trip, Sheldon mentions he's applied for a one-way colonize Mars. Amy is angered to learn Sheldon has made a huge decision that could see him leave Earth forever without even discussing it with her. Back at the apartment, Leonard tells Penny he bought her a Valentine's Day gift but was too embarrassed to give it to her. When he explains he went to an adult store and bought a body paint kit and canvas, Penny is excited to try it out.

Bernadette is doing their taxes while Howard plays video games. Raj phones  Howard to tell him he's alone at Emily's. As Raj snoops around her bedroom, he accidentally breaks the door off one of her drawers and is freaked out that she'll know he was snooping. Elsewhere, as Leonard and Penny appraise their paintwork, they are disappointed to see that their canvas doesn't show much action. As they don't think of themselves as an old couple, they decide to do it again and make more of an impression.

When Sheldon and Amy return from the pet store without a turtle, Amy is still upset about Sheldon's unilateral decision to go to Mars. As Sheldon makes her tea, Amy asks him why he wants colonize another planet. Sheldon explains his scientific interest and shows her the video application he made for the project. Meanwhile, while Raj tries to fix the broken drawer with help from Howard on the phone, Emily returns home. Raj confesses to Emily that he was snooping around her bedroom, as Howard and Bernadette listen in on their argument over the phone.

Leonard and Penny are impressed with their canvas following their second go. Although Leonard wants to hang the painting somewhere, Penny is uncomfortable with what it represents, so she suggests they give it to Sheldon and claim William Shatner painted it. Back at the apartment, Amy decides to leave after telling Sheldon she thought them getting a turtle meant something but his decision to go to Mars shows it didn't. Sheldon follows after her, telling her getting a turtle meant a great deal to him, too. When Sheldon asks her if she wants him to withdraw his application, Amy tells him they should be planning their future together.

When Sheldon suggests he and Amy could go to Mars as a couple, Amy is intrigued. Sheldon tells her if he's going to a barren, lifeless environment where the chances of survival are slim, he wants her there with him. Sheldon and Amy return to the apartment to fill out her application. Elsewhere, Raj thanks Emily for making up with him after their first argument as a couple. Before they fall asleep, Emily asks Raj if he snooped around her closet. When Raj says he didn't, Emily tells him not to worry about it, leaving Raj wide awake wondering what's in her closet.