Twenty years ago, Twilight Velvet, notorious pirate, thief and pregnant, was sent to swing at the gallows for her crimes against the Royal Crown. Or that's the story that was told to the public. Princess Luna has a secret. And that secret's name is Nyx.

Nyx is listed in Pony Mythology as the Goddess of the Underworld. Just one thing, it isn't a myth. Twilight Velvet and her husband visited her mother when her unborn was declared lost. In desperation, Velvet struck a deal with her mother and Nyx made sure Twilight was born healthy and happy. On a rickety pirate ship. On the waves of the Sea of Souls. In the Underworld.