But with “Ice Cream Man,” Roth tries to go “over the line” in a way that’s shamelessly derivative, jaw-droppingly bare-bones basic as filmmaking, and way too ludicrous to scare you. But this ice-cream man is a sinister psycho creep. But those movies all tower over “Ice Cream Man,” a one-joke piece of hyped-up kiddie zombie splatter schlock. What “Ice Cream Man” comes down to, after a while, is an army of teen actors glowering in zombie ice-cream-barf makeup. With a slight nudge, “Ice Cream Man” could be a “Saturday Night Live” horror trailer.