Howard: Hello. [dressed like Sheldon, imitating him]
Sheldon: Hello.
Howard: I see you are dressed as Doc Brown from Back to the Future. May I assume that Amy is going as his wife, Clara Clayton, from Back to the Future Part III?
Sheldon: She is. Did you do something different to your hair?
Howard: Yes.
Sheldon: Looking good.

Professor Proton: Hello, Sheldon.
Sheldon: Hello, Arthur. Now, I'm confused, usually when you appear to me in my dreams, we're on the planet Dagobah.
Professor Proton: This is Dagobah.
Sheldon: I didn't know that Dagobah had delicatessens.
Professor Proton: Not good ones. Whatever you do, don't order the Reuben.

Sheldon: I'm having a problem in my marriage. I've upset my wife and I don't know how to make it right.
Professor Proton: (chuckles) And you're and you're coming to me for advice? I-I upset my wife every time I woke up in the morning.

Sheldon: I'm not coming to you, you're just a manifestation of my subconscious. I mean, I'm actually coming to me.
Professor Proton: So you know everything I'm going to say.
Sheldon: Yes, but it sounds wiser from you because you're old and glowing.

Professor Proton: Rule number one in a marriage: don't go to bed angry.
Sheldon: That makes sense.
Professor Proton: Rule number two in a marriage: if you don't recognize the shoes under your bed, they're not your shoes.
Sheldon: Because they're her shoes?
Professor Proton: (sighs) N-Never mind, just-just go with rule number one.
Sheldon: Thank you, Arthur.
Professor Proton: Uh, before you go, can I ask you a question?
Sheldon: Of course.
Professor Proton: Does this look lean to you? I ordered lean.

Sheldon: Amy. Wake up. Amy.
Amy: What? What's wrong?
Sheldon: We can't go to sleep angry with each other.
Amy: Why not?
Sheldon: It's rule number one. I'd tell you rule number two, but it's confusing.

Amy: Sheldon, go to sleep.
Sheldon: Amy. [tapping her three times] Amy. [tapping her three times] Amy. [tapping her three times]
Amy: You cut that out!
Sheldon: Oh, good, you're up.

Sheldon: No, Professor Proton came to me in my dream and said we can't go to sleep angry.
Amy: Are you sure that's what he said? Close your eyes, double-check.

Amy: Okay, listen to me. I love working with you, but you have to understand how scary this is for me.
Sheldon: Why?
Amy: Because I don't want to get lost in this relationship. And when you pulled me off my project, it seemed like my biggest fear was coming true, the-the things that are mine are getting subsumed into the things that are ours.
Sheldon: I wouldn't want that to happen, either. Thank you for explaining, and for using the word "subsume," that's one you don't hear enough.

Amy: What are you doing now?
Sheldon: Looking for shoes.
Amy: Why?
Sheldon: When your favorite ghost tells you to do something, you do it.

Penny: So when was the last time you saw Howard in his astronaut uniform?
Bernadette: About a week ago.
Penny: Really? What was the occasion?
Bernadette: Date night. We do a little role-playing.
Penny: What role do you play?
Bernadette: (Russian accent) I am Ykatarina Nazdorovya, lonely Russian cosmonaut who is expert at physics and making love.
Penny: Okay, that just made the next hour really weird.

Raj: Good evening, I am Dr. Rajesh Koothrappali, and usually I take you on a trip through the stars, but tonight, we'll begin our journey much closer to home, 220 miles straight up to the International Space Station, which is manned by a team of brave men and women.
Bernadette: (Russian accent) Flexible men and women.
Penny: [to Leonard] Switch with me.

Raj: And we are fortunate to have one of those men here with us tonight. Please welcome to the Griffith Observatory astronaut Howard Joel Wolowitz.
Bernadette: [fanning herself with the program] Kak horosho.
Leonard: What is she ta-
Penny: Don't ask.

Howard: Thank you, Raj, that was a really nice introduction.
Raj: Well, it's from my heart. So, Howard, you are in an elite group. Only 232 people have ever been on the International Space Station. How does that make you feel?
Howard: Honestly, lucky. Most astronauts have to train their whole lives. I was just in the right place at the right time.
Raj: Oh, please, luck had nothing to do with it. You people need to know how impressive this man is. He was up there because he's the only one qualified to install a piece of equipment that he designed.
Howard: Thanks, but if you want to talk impressive, this guy right here discovered a planetary object outside the Kuiper belt.
Raj: He worked on the Mars rover.
Howard: He helped launch the New Horizons space probe.
Raj: He went to space on a Russian rocket.
Howard: And I was scared the whole time.
Raj: And I was scared for you, but also proud.
Howard: Wow. I don't think you've ever said that to me before.
Raj: I should have, and I'm gonna say it again. I'm proud of you. You're my best friend, and I love you.
Howard: Aw, Raj, I love you, too.
Bernadette: What is happening?
Raj: Bring it in, spaceman, you've been cleared for landing.

Bernadette: Can you believe these two?
Leonard: (crying)
Bernadette: Are you crying?