(Sherlock-MLP crossover) Dr. Greenheart and his mysterious new flatmate, Eagle Eye, investigate a strange murder that puts them on a trail of an intriguing plot that twists across the city of Londerby.

The Doctor, Derpy and the Mane 6 go back time to the Pre-Classical era in order to stop a great evil from altering history, and their adventure creates the Elements of Harmony.