DOCTOR: No, of course not. We haven't come to take anything. We genuinely are interested in space travel. Why, especially a thing like this. This is superb.

ELDRED: Yes, magnificent. It was to have been the vehicle to take man beyond the moon. T-Mat put an end to all that.

DOCTOR: You mean this model's been abandoned? But it's speed and stability concept alone, it's a tremendous advance in rocket design.

ELDRED: Exactly! Exactly! Here, let me show it to you. Let me show it to you.

(Eldred puts down his gun and helps the Doctor with the ion jet rocket model.)

DOCTOR: I'll give you an hand, here we are. Oh yes, this is superb. My word.

ELDRED: And the secret, the real breakthrough, was a compact generator of enormous power.

DOCTOR: I see. And these must be the secondary electrode accelerators.

ELDRED: Yes. You see it beat the problem of the neutral caesium ions. And incidentally, it magnified the g-thrust to fantastic proportions!

DOCTOR: That was awkward. What did you do about that?

ELDRED: Well, I'll show you. Come with me, I'll show you. Look.

(Eldred and the Doctor go to the back of the room.)

DOCTOR: What have we go here? Ah, blueprints!

JAMIE: Look at them, like a couple of kids.

ZOE: Yes. You can tell he's almost in love with that rocket.

JAMIE: Shush!

ELDRED: That's not surprising. I designed it. I've been in rocketry all my life. My father engineered the first lunar passenger module, and I travelled on the last trip back to Earth. Before it all finished.

ZOE: Before all what finished?

ELDRED: Space travel.