Question: Who is known for their prolific work in the horror film genre, Valie Export or Gary Sherman?
Sentence (from "Poltergeist III"): Writers Michael Grais and Mark Victor, who wrote the screenplays for the first two films, did not return for this second sequel; it was co-written, executive produced, and directed by Gary Sherman, and was released on June 10, 1988 by Metro-Goldwyn-Mayer Pictures.
Relevant evidence: No