To save her sister and her faithful student, Celestia herself must travel into the ancient tunnels beneath the ruined castle in the Everfree Forest. She, and the guards who accompany her, must face the dark, twisting corridors. Still, what was Luna and Twilight's purpose at the old castle? Why were they unable to return of their own accord?

And what watches Celestia from beyond the light's edge?

This story is a sequel to Into The Depths

The horrors of the catacombs have turned to distant memories for Celestia, Twilight, and Luna. Discord’s change of heart and Twilight’s coronation have helped to ease and erase the mental scars from that harrowing night. The three princesses can even smile and laugh as Nightmare Night moves into full swing.

Yet, it should never be forgotten that those who have been touched by Tirek are forever within his grasp.