Sherlock and Watson are transported to Equestria, where they stumble across a case steeped in magic, lies and death.

After Marzia is kidnapped and PewDiePie is turned into a pony, our foul-mouthed Swedish hero must navigate a deadly maze to save his girlfriend and get home!

When a dead pony turns up in the alley next to Sugarcube Corner, accusations begin to fly, the Cakes are arrested and it's up to a smart-ass detective and a determined teenage Pumpkin Cake to solve the case.