Percy and Toby share ghost stories about an old folktale on Sodor known as "The Ghost Engine". Thomas dismisses it as nonsense, but as the night goes on, the three engines find themselves drawn to a creepy abandoned mine where some kind of force seems to be playing mind-games with them. This soon drags some of their friends to find them at the same mine, where their worst nightmares seem to be coming to life in a series of mazes beneath the ground.
