When a character previously positioned as a Big Bad is revealed in fact to be a Disc One Final Boss, The Man Behind the Man shows his (or her, or its) face. The Man has deeper problems, deeper motives and so much power that the heroes will have to go through another round of dungeon diving just to stand a chance. When he reveals his reasons for being evil, expect the theme of the plot to unfold quickly and dramatically. Compare and contrast Bigger Bad, where a villain more powerful than the Big Bad exists, but is either not personally involved in the plot or is not a "person" to begin with.