By the year 1991, Wes Craven had already solidified his place in the Hollywood “master of horror” pantheon. But for his third act, the “Nightmare on Elm Street” creator began asking, “What’s the point of all this slashing?” as he embarked on a series of socially critical and self-reflexive scary movies: “The People Under The Stairs” (1991), “New Nightmare” (1994) and “Scream” (1996). For your Halloween episode, we dive in.