Kid, Liz and Patti head over to a train station in the Sahara desert to investigate a possible demon tool being the power source of an unstoppable train known as the "Runaway Express". They find a little child at the station and end up facing the Fisher King, an Arachnophobia assassin, wanting to take over the tool for Arachne. The child is also revealed to be one of the Mizune family members, and all three sides struggle to get their hands on it. The Fisher King ends up being defeated by Kid, but he also ends up knowing his father had something to do with Eibon in the past, and decides to investigate it in the library, only to discover the book about Eibon had been requested two months previous by a person with an "M" signature. Kid deduces that the M stands for Medusa, as the book was checked out on the day the kishin was revived.