The mysterious race of darklings emerges from the shadows. Ancient foes that Equestria fought a millennium ago awaken as Twilight Sparkle discovers secrets long forgotten by ponykind. Aided by the denizens of the plane of shadows, she goes on a journey to uncover what was hidden during the war. The sun regent keeps quiet, shutting herself away in fear of an all-encompassing gloom - it is up to Twilight to discover what is going on behind the veil.