From the introduction:
Background: It is the spring of 1889 and London is beset by a plague of disappearances near the riverfront. Rumors of a "Demon of Fog: are being played up by the press and passed off by the police as wild rumors. Scotland Yard was unhappy that no sign of ransom, abduction for slavery, or bodies of victims had been found. None of the victims had anything in common other than being last seen in the riverfront area. Because of this atmosphere of fear, London is downright scary (-1 to Guts rolls). Beginning players can either be English natives or visitors from other nations in for their own personal reasons.
Setting: Originally designed as an introduction to Savage Worlds and the Space 1889 Victorian age science fiction adventuring, this adventure can be used without the Space 1889 background. Just ignore any references to travel to the other worlds of our solar system and play it as a Victorian Pulp setting. Players should be humans and the Arcane Backgrounds should be limited to Weird Science unless the GM says otherwise.