In search of gems to complete her ornate Nightmare Night costume, Rarity accidentally finds herself transported to a world where a holiday not unlike Nightmare Night is less an event than a way of life - and her friends soon follow in hopes of rescuing her. Or, to put things more lyrically....

It was some time ago, but not too long, you see?
In a place that perhaps you have seen on TV.

For this story spans places far from pedestrian,
Crossing spooky and dark with bright and Equestrian.

Now, you may be asking how that crossing was done.
If you are not, I'd say it's time you begun!

(An excellent talking-book version of this story can be found here.)