Foals are being snatched away in the dead of night, and vanishing without a trace.

Apple Bloom wakes up to find a mysterious pony standing at the end of her bed, a mare with glowing white fur, blazing eyes, and a mane and tail made from stardust. It gestures towards the door and taps its hoof impatiently. With a jolt, Apple Bloom realises that it wants her to follow it...