As Davey O'Shea works as a Sparker for Nikola Tesla, implementing his wireless electricity technology to the streets of London in 1888, he is also on the lookout as a detective for Scotland Yard during the peak of Jack the Ripper's gruesome spree. Visited by a strange man one night out on the job, Davey is presented with the legendary sword, Excalibur, and upon touching it, learns he is a descendant of King Arthur himself. Now armed with the knowledge of his famed ancestor, Davey joins forces with other descendants of the Round Table to search for King Arthur's true nemesis. Always two steps behind, however, and with more of the Ripper's victims piling up, Davey must find a way to get ahead in order to stop both past and present adversaries.