Strategist Dalek

It's bigger on the inside!

The Doctor: It's a lot to take in, isn't it? Tiny box, huge room inside; what's that about? Let me explain...
Rory Williams: It's another dimension.
The Doctor: It's basically another dimen- what?
Rory Williams: After what happened with Prisoner Zero, I've been reading up on all the latest scientific theories. FTL travel, parallel universes.
The Doctor: I like the bit when someone says "It's bigger on the inside!" I always look forward to that.