Captain Richard Burton and John Hanning Speke have successfully returned from their quest for the Source of the Nile. But Speke has secret, nefarious plans and soon, the undead began stalking London's sewers. The Damocles Institute of Research and Exploration—DIRE—sends their two best operatives to investigate. It doesn't take long for Jonathan Blackthorne, aka the Astounding Blackthorne, Magician Extraordinaire, and his fiancé Lady Rose Blakeney-Barrington, brilliant scientist and inventor, to uncover the most dastardly plot imaginable. Can they and the other agents of DIRE save London before everyone becomes a shambling revenant?