The Doctor: [having fled into the TARDIS] Well, Sergeant, aren't you gonna say that it's bigger on the inside than it is on the outside? Everybody else does.
Benton: [standing amazed] It's pretty obvious, isn't it?
The First Doctor: Oh, so you're my replacements - a dandy and a clown. Have you done anything?
The Second Doctor: Well, we've assessed the situation...
The First Doctor: Just as I thought - nothing.
Jo Grant: I hate to ask, but who was that?
Brigadier Lethbridge Stewart: The thing is, Doctor, is there anything I can do?
The Doctor: Yes, pass me a silicon rod, will you?
[a rod is passed to the Doctor, who merely stirs his coffee with it]
Brigadier Lethbridge Stewart: Yes, what I meant was is there anything that UNIT can do about this space lightning business?
The Doctor: Lightning? Yes, I suppose it could look like lightning, only it isn't. No, if there were such a thing, I'd say it was compressed light, a sort of controlled superlucent emission.
The Second Doctor: You see, he is one of me.
Jo Grant: Oh, I see. You're both Time Lords.
The Second Doctor: Well, quite. Well... not quite.
Jo Grant: Oh.
The Second Doctor: Not JUST Time Lords, we're the SAME Time Lord.
The Doctor: Now, please, you're only confusing my assistant. Jo, it's all quite simple: I am he and he is me.
Jo Grant: And we're all together, goo-goo-g'joob?