The Twilight Zone (1985) 1x18

A young boy is left to care for his old, scary grandmother. He finally confronts his fears and steps up to her, finding that she has no pulse. Then Gramma reaches out and grabs him... A screenwriter is having writer's block when strange impish creatures start haunting him. Sadly, only he can see them. An actor arrives at a radio station to perform a radio play. An old voodoo stick is accidentally activated and the play becomes more real that anything anyone expected.