Four Favorites #23 (1946)

In the eerie halls of the Franklin Historical Museum, Magno and Davey investigate a series of mysterious, violent crimes committed by invisible assailants wielding medieval weapons—just as a rare incantation hidden among ancient documents begins to stir something long buried. As the night unfolds, the duo confronts a chilling possibility: the spirits of a long-dead band of ruthless knights may have been awakened, their ghostly forms wreaking havoc in the modern world.