A young pegasus wakes up alone in a field with no clue as to how she arrived in Equestria.
She was human once - she thinks - but her memory is tattered and unreliable, only coming to her in sharp, burning flashes. She can't even remember her name, and now she has to piece together the events that led her across time and space, if she ever hopes to return home.

Meanwhile, deep underground in the tunnels below Canterlot, the Star Bright Network crafts a plan to break the barrier of reality, and they think they've located the last missing piece of the puzzle.

In between it all, the Doctor and his bubbly companion investigate the strange energy that has been flowing out of Equestria's capital city. Something big is on its way, and their universe will crumble unless they can stop it in time.