It's 1895 and Toronto City Council is considering changing its electricity supply from direct current (DC) to alternating current (AC) to take advantage of the new electric generation plant at Niagara Falls. There's a lot of money at stake and the owner of Toronto Electric and Light, Daniel Pratt, has been holding public demonstrations on the dangers of AC current by electrocuting dogs. When Miss Toronto Electric and Light, Alice Howard, is electrocuted at one of these demonstrations, Detective William Murdoch cannot help but wonder if she was murdered. Assisted by the local coroner Dr. Julia Ogden and inventor Nikola Tesla, Murdoch applies his scientific approach to policing to solve the crime. Constable George Crabtree meanwhile pursues his own theory that animal rights activists may have been behind the death.