Serum obtained from a brain after a mass murder transforms the good Dr. Jekyll of London into the evil Mr. Blood.

A deranged 15th Century prison colony chaplain exploits his power to get money for his church including murder and grave robbing committed by his vampire mistress and one-eyed hunchback assistant.

In Medieval England, a sadistic duke plots to kill off all the heirs to the throne so he can claim the crown for himself.