The Industrial Revolution smothers Equestria, and the only way to gain the resources needed to power the giant machines being created is by pleasing the mountain owning Gryphon Empire. But when Celestia holds a grand fair for the Empire in Canterlot, murders become rampant, and the new secret service and the Twilight Sparkle must uncover the murderer before Equestria is crushed under the weight of their new machines.