Life in Stable 105 was peaceful, even boring. But after spending 200 years underground has led to the scant population becoming dangerously inbred. Then suddenly one day strange ponies find their way through the caves and tunnels into the Stable.

Fearing the worst, Head Security Officer Jasper "Rusty" Pie is sent topside to figure out what's out there before the rest of his Stable can leave their decaying home for a life on the Surface.