Complex sentence: In modern times, zombies became a popular subject in horror fiction, largely because of the success of George A. Romero's 1968 film "Night of the Living Dead" and they have appeared as plot devices in various books, films and in television shows.
Split into simpler sentences: In modern times, the term "zombie" has been applied to an undead race in horror fiction, largely drawn from George A. Romero's 1968 film "Night of the Living Dead". They have appeared as plot devices in various books, films and in television shows.