The air was musty, as if something malevolent had crawled in there a million years ago and given birth to shadows and silence and dust.

And then, perhaps for the first time in centuries, a faint echo ran through the corridor; a sound like distant drums, or perhaps a thunderstorm far away across a black sea. The air in the corridor swung apart like a grimy curtain to reveal a large blue box with a flashing light on top. Momentarily the thunder crashed overhead, as if something infinitely heavy had come to rest.