As a child I always steered clear of science fiction, but in the autumn of 1977 the bow-wave of publicity for the first Star Wars movie had already reached me, so I was eager for anything science-fictional.

Sometimes, on our way through the world, we meet someone who touches our heart in a way others don't.

Even tiny children looking at a picture book are using their imaginations, gleaning clues from the images to understand what is happening, and perhaps using the throwaway details which the illustrator includes to add their own elements to the story.

It was a dark, blustery afternoon in spring, and the city of London was chasing a small mining town across the dried-out bed of the old North Sea.

But boys will be boys, even the ones who are only girls dressed up: That's one of the rules of the world.

The one thing worse than an enemy is a friend turned false.

Moving cities are a fairly hoary old sci-fi trope - I seem to recall they were always cropping up on Doctor Who when I was young, though I may be misremembering.