Jackaby (Jackaby, 1)

A serial killer is on the loose in New Fiddleham, New England, 1892. Abigail Rook, a newly hired assistant, helps R. F. Jackaby, an investigator of the unexplained. The police are convinced it's an ordinary villain, but Jackaby--who has the ability to see supernatural beings--is convinced that the foul deeds are the work of a supernatural creature.