Sherlock Holmes gets a visit from the Mane 6 about the mysterious absence of their friend Rainbow Dash. At the same time, he is presented with the numerous bodies of young pegasi in Cloudsdale. Are they connected? It seems he and Dr. Watson have their work cut out for them.

Based off of the fanfictions of the Rainbow Factory and Pegasus Device. Also based off songs. In fact, Pinkie Pie sings a bit of the Pegasus Device, so brace yourself.