The dictaphone

The man appeared out of the blue, right in the middle of the street, with a strange sparkling sound. Nobody saw him, as the night was dark and the good people sleeping.

Except the small barks of a dog in a nearby garden, the street was perfectly quiet, and the man smiled as he went to the closest mailbox. Rummaging through one of the pockets of his huge coat, he finally found a small package, and muttered something before putting it in the mailbox. Looking at the house in front of him, he made a wicked smile, and took a step back before disappearing again in the same sparkling sound.

On the package, it was written :

"To the one who will find this
Here's a present, just for you
Coming right from the abyss
May all your wishes come true"

And inside, a curious dictaphone was waiting in a box.

The next morning, someone finds the package... but who is it ?