Debra Hart leads a rather plain life, discounting the disasters caused by her clumsiness on a daily basis. Luckily she meets a man who adds a bit of excitement to her life, though often in the form of other-worldly beings that want to kill them both.
The humble mailmare of Ponyville wakes up one day to go to work. A nice, normal, everyday sort of day...until that day, and her world, changed forever.....
The Doctor is confused. He was just having a lovely time in his TARDIS, when all of the sudden, he regenerates when the old box transports itself to a mysterious land called Equestria.
Derpy wishes to go somewhere relaxing. The Doctor is willing to grant her wish but the unexpected appearance of a unicorn named Twilight Sparkle and the TARDIS unexpectedly taking them 600 years into the future changes his plans.
Twilight, Rainbow and Applejack travel 3000 years into the past with their new friend the Doctor, to the ancient city-state of Roan. They meet the famous Leonard DiHoovsie, and find themselves embroiled in a deep mystery with dark implications.
After the harrowing events of "Traveller," the Doctor is forced into having some downtime in Ponyville while the TARDIS rests. Meanwhile, Twilight goes to confide in her beloved mentor, but ends up learning far more than she expected.
Following an accident with the TARDIS, the Doctor finds himself in a strange universe with a new body that he didn't gain from regeneration. Meanwhile, a pegasus named Derpy is unaware that her life is about to change forever.
The Doctor has been living in Ponyville for several peaceful weaks, but the peace is shattered when a stallion from an alternate dimension named Clockwork appears.
The Doctor, Twilight, and Derpy arrive in the England of the Doctor's universe on Christmas Eve of 2010. What waits for them includes an icy storm, something from Derpy's past, and a reunion with a lost friend.
The Doctor must solve the secret behind a mysterious mare named Colgate if he wishes to save her from an ancient creature, as well as save Twilight and Pinkie Pie from the past.
The Doctor, Twilight, and Derpy end up accidentally taking a detour on their way to the Doctor's universe and instead end up in a reality where they are merely fictional characters.