Sheldon: Hello, I'm Dr. Sheldon Cooper.
Amy: And I'm Dr. Amy Farrah Fowler.
Sheldon: Based on the glowing reception of our recent Behind the Flags retrospective, we thought you might like to see how it all came together.
Amy: So welcome to tonight's episode,
Both: Fun with Flags - Behind the "Behind the Flags: A Retrospective" Retrospective.

Zack: Do you have a bodyguard to keep spies away?
Leonard: I have Sheldon, that keeps most people away.
Zack: I miss that guy. He's like the Swedish Chef Muppet. I don't know what he's saying, but he's funny.
Leonard: Oh, I know what he's saying, and he's not, he's not funny.

Bernadette: So you wanted to learn something physical and you came to Howard Wolowitz?
Howard: Hey, the circus arts are very physically and mentally demanding. Have you ever tried to juggle?
Bernadette: Yes, I'm juggling my love for you and my embarrassment of you right now.
Howard: And it's hard, isn't it?

Sheldon: Shall we?
Raj: Oh, my God. It's light, it's flaky, it's buttery. You don't need to have sex with him, just eat one of these.

Sheldon: What happened to me? I used to excel at these things.
Howard: Kids are always better at video games.
Sheldon: Well, I don't like it.
Leonard: If it makes you feel better, you still dress like a child.

Raj: Well, I know how you feel. I tried one of those electronic Japanese toilets, practically shot myself across the room.

Zack: Penny?
Penny: Oh, Zack. Hey.
Zack: What are the odds of running into you here?
Penny: Well, it's a bar, so pretty good.

Zack: How about you? Hey, how's Leonard? Is he still smart?
Penny: Yes, yes, he's working for the government on an infinite persistence gyroscope. Of course, the first time I say it right, he's not even here.

Howard: Now, this is rare. I don't know which one of you I want to stop talking first.
Sheldon: The theory is that if you really tax your brain, the neurofibers will become thicker and the glial cells more lustrous.
Raj: Like JLo's hair.
Howard: Boy, it is neck and neck right now.

Raj: If you really want to challenge yourself, you could learn to speak Hindi.
Sheldon: Jab mein aat saal ka tha Maine seekha tha.
Raj: Could you say that in English? I actually, I never learned Hindi.

Penny: Hey, you ready to go?
Leonard: Yeah, I guess.
Penny: What's the matter?
Leonard: Honestly? It's a little strange having dinner with your ex-boyfriend, and it's not like we have a lot to talk about.
Penny: What? He loves you, okay? And he's interested in your work. You could talk about the infinite perspective -- I swear I know it.

Raj: You want a real challenge, try keeping me from eating more of these.
Sheldon: You're just using food to mask the fear that you're fundamentally unlovable and therefore going to be alone forever.
Raj: Damn it, he's good at that, too.

Zack: So, Penny, what's going on with you? How's the job?
Penny: Uh, it's okay, I'm still in pharmaceutical sales.
Leonard: She's doing amazing. She can actually make a side effect, like 10% chance of liver failure, sound like a 90% chance of liver success.

Penny: Yeah, lying isn't my favorite part of the job. Actually, I'm not crazy about a lot of it.
Zack: Hey, if you're not happy there, I've been looking for a new head of sales at my company. And we don't sell drugs, just menus, so the only lie you'll be telling is we print on recycled paper. We don't.

Howard: All right, this is everything. What do you want to learn?
Sheldon: It really doesn't matter, as long as it's challenging.
Howard: Okay, well, how about, oh, I teach you some close-up magic.
Sheldon: Howard, I'm trying to make myself uncomfortable, not everyone else.