21. Tap, Tap, Tap [Mystery]
A character begins waking up tired in the morning, despite having slept through the night. After a night or two, the character becomes aware that there is a tapping sound pervading his dreams. This tapping is fairly rhythmic, but inconsistent, as though its source were a person working steadily and taking occasional breaks of less than 30 seconds. After another night or two, the character begins to feel the effects of fatigue. The next night, the character dreams he is exploring an extensive underground complex in search of the source of the tapping but does not find it. After suffering under the effects of this dream for another evening or two, he wakes suddenly one night to find he can still hear the tapping, though it is faint and far away.