Mickey Smith: Wait, the Tardis, you can't just leave it. Doesn't it get noticed?
Jack Harkness: Yeah, what's with the police box? Why does it look like that?
Rose Tyler: It's a cloaking device.
Doctor: It's called a chameleon circuit. The Tardis is meant to disguise itself wherever it lands. Like, if this was ancient Rome, it'd be a statue on a plinth or something. But I landed in the 1960s, it disguised itself as a police box and the circuit got stuck.
Mickey Smith: So, it copied a real thing? There actually was police boxes?
Doctor: Yeah, on street corners. You could phone for help before they had radios and mobiles. If they arrested somebody, they could shove them inside till help came. Like a little prison cell.
Jack Harkness: Why don't you just fix the circuit?
Doctor: I like it, don't you?
Rose Tyler: I love it.
Mickey Smith: But that's what I meant, there's no police boxes anymore so doesn't it get noticed?
Doctor: Ricky, let me tell you something about the human race. You put a mysterious blue box slap-bang in the middle of town, what do they do? Walk past it. Now, stop your nagging, let's go and explore.
Jack Harkness (about a soldier): Trust me, you're not his type. I'll distract him. Don't wait up.
Doctor: Relax. He's a 51st century guy. He's just a bit more flexible when it comes to dancing.
Rose Tyler: How flexible?
Doctor: By his time, you lot are spread out across half the galaxy.
Rose Tyler: Meaning?
Doctor: So many species, so little time.
Rose Tyler: What, that's what we do when we get out there? That's our mission? We seek new life and... and...
Rose Tyler: What? Are you telling me you do dance?
Doctor: 900 years old, me. I've been around a bit. I think you can assume at some point I've danced.
Rose Tyler: You?
Rose Tyler: Doesn't the universe implode or something if you dance?
Doctor: Well, I've got the moves but I wouldn't want to boast.
Jack Harkness: It's the special features, they really drain the battery.
Rose Tyler: The battery? It's so lame.
Jack Harkness: I was going to send for another one but somebody's got to blow up the factory.
Rose Tyler: I know. First day I met him, he blew my job up. That's practically how he communicates.
Doctor: Can you sense it?
Jack Harkness: Sense what?
Doctor: Coming out of the walls. Can you feel it? Funny little human brains. How do you get around in those things?
Rose Tyler: When he's stressed, he likes to insult species.
Doctor: Rose, I'm thinking!
Rose Tyler: He cuts himself shaving. He does half an hour on life-forms he's cleverer than.
Jack Harkness: It's a con. I was conning you. That's what I am, I'm a con man. Thought you were Time Agents. You're not, are you?
Rose Tyler: Just a couple more freelancers.
Jack Harkness: Oh! Should've known, the way you guys are blending in with the local color. Flag Girl was bad enough, but U-boat Captain?
Jack Harkness (to Doctor): Jack Harkness. I've been hearing all about you on the way over.
Rose Tyler: He knows, I had to tell him. About us being Time Agents.
Jack Harkness: And it's a real pleasure to meet you, Mr. Spock.
Doctor: Mr. Spock?
Rose Tyler: What was I supposed to say? You don't have a name. Don't you ever get tired of "Doctor"? Doctor who?
Doctor: Nine centuries in, I'm coping.