You've found an "interesting" book recently. You don't know what it is, or why it was hidden in the back of Twilight's library, but you feel so compelled to read it. And keep reading it. And keep reading it...
After breaking her leg in the middle of the Everfree Forest, Applejack is forced to take shelter with Rainbow Dash in an abandoned cabin in the woods. Historically, this sort of thing has only ever ended well.
Have you ever felt yourself suddenly terrified, for no apparent reason at all? We all know that 'gut feeling' isn't a real thing, and that there's nothing to be afraid of. It doesn't help though, does it?