Racine, Wisconsin, the 1950s.

When several mutilated bodies of thugs are found in a parking structure downtown, Detective Garfield Teague suspects that it is something other than a drop off gone wrong. His suspicions are confirmed when details arise regarding a sword- wielding vigilante seemingly with the same objective as the police; finding the clandestine criminal organization known as The Black Diamond. With every lead a dead end, and each clue creating a more sinister tableau, Teague must ask himself two questions. Who is flooding the streets with cocaine, and who stalks the night wearing terrifying mask of fear?