Nightmare Moon reigns over an Equestria veiled by eternal night, forcing the ponies to worship her and shower her with tribute, even as they struggle to live without the Sun. Princess Celestia has been sealed away in the Moon, and the Queen of Nightmares has crushed all resistance underhoof. At least, that's what some ponies want her to think. A loose network of rebels works under perpetual cloak of darkness to see the Sun rise again... and a brief visit from a timeline-hopping alicorn might provide just the edge they need.