Unexplained noises are best left unexplained.

“He held the book up to his nose. It smelled like Old Spice talcum powder. Books…”

“Then there's no point in our being logical, is there?" said Jonathan..."What do…”

“Suddenly the air got colder, and a black cloud appeared - the black cloud that …”

“He invented the Fuse Box Dwarf, a little man who popped out at you from behind …”