Speaking of the third movie, Nick Roche posted on Twitter last week that he had a friend who had the odd belief that at the end of the trilogy Doc was going to the moon.

I responded that I also thought Doc was going to the moon, and he thought I was joking. But I explained that no I've always thought this was the case. Actually until his tweet I never knew people thought anything else or that it was an ambiguous scene.

Doc and Clara talk about going to the moon one day earlier in the film. Doc says he's not going to the future as he's already been there. The train is airtight. The train converts and flies off into the sky. I never, ever thought they were time travelling until Nick's post made me doubt the way I've always interpreted that scene. (I guess in the future trains would fly but he just said he's not going to the future!)

(The other thing that I realised on BTTF Day was that the film features a Doctor who travels in time and space with a school teacher named Clara... which is a bit familiar these days!)