Enter the Underworld of Chicago.
Detective Danny Mancini is on a case, following a murder suspect. When he catches him, he finds out that the perp isn't even human: he's a two-hundred-year-old rogue vampire.
The Captain doesn't believe him, and puts him on early retirement, despite his many years of service to the Chicago Police Department, which sends him into a downward spiral.
Two years later, Danny gets an invitation from the beautiful, mysterious, and slightly unsettling Special Agent Angelica Cross to join a secret branch of the FBI to help her track down Vincent, the wayward vamp.
But renegade werewolves, meddling immortal witches, and Danny's strange visions of a life lived a century ago with Angelica make things more difficult than it should be.
