The actor ought to save his prayer because God is not listening. "He that turneth away his ear from hearing the law, even his prayer [shall be] abomination" (Proverbs 28:9). As we are to "judge righteous judgment" (John 7:24) and "by their fruits ye shall know them" (Matthew 7:20), the participation in the movies shows that he actively supports Satan side. God is not into vampires and werewolves.