At the end of A Feast Unknown, Grandrith and Doc Caliban (a thinly disguised Doc Savage) cease fighting each other upon learning that their personal war and indeed their entire lives were engineered by the Nine, a megalomaniacal and powerful secret society. The two men have a sexual affliction in common; they are impotent except when performing acts of violence; a temporary side effect of a serum that grants them eternal life—another product of the Nine. Angered by the ways they have been manipulated, the two heroes split up to overthrow the Nine, ultimately meeting up at the end. Lord of the Trees shows the story from Grandrith's point of view. The Mad Goblin tells the same story from Doc Caliban's viewpoint.
