In 1888, Jack the Ripper – lamenting the fact that his ritualistic murders have not unlocked a mystical power that he believes to exist – prepares to perform the ritual upon himself at the expense of his own life. A man named Legion appears and tells Jack that the power he seeks does exist and offers to share this power with him if Jack constructs an insane asylum for like-minded killers in Deadside – the land of the dead. Proclaiming "for we are many!", Jack commits suicide.

In the present day, Michael LeRoi becomes the current Shadow Man – a lineage of voodoo warriors who protect the world of the living (known as Liveside) from threats crossing over from Deadside – after the voodoo priestess Mama Nettie bonds the Mask of Shadows to him. Nettie has a prophetic dream that Legion is preparing to usher in the Apocalypse by claiming the Dark Souls – the immortal souls of damned warriors – and using them to create an immortal army and send it into Liveside. Nettie reveals that Michael cannot stop the Five, a group of serial killers recruited by Legion, without his powers. The Five, who each have a Dark Soul within them, are hiding in Liveside, where Michael's powers do not work during the day. Michael travels to Deadside with the use of his dead brother's teddy bear, which serves as a link between both worlds.