"When the Guide moved on, taking its building with it, it left a little like a thief in the night. Exactly like a thief in the night in fact. It usually left in the very early hours of the morning, and the following day there always turned out to be a very great deal of stuff missing. Whole cultures and economies would collapse in its wake, often within a week, leaving once-thriving planets desolate and shell-shocked but still somehow feeling they had been part of some great adventure."