Prequel
A prequel is a literary, dramatic or cinematic work whose story precedes that of a previous work, by focusing on events that occur before the original narrative. A prequel is a work that forms part of a backstory to the preceding work. The term "prequel" is a 20th-century neologism from the prefix "pre-" and "sequel". Like sequels, prequels may or may not concern the same plot as the work from which they are derived. More often they explain the background that led to the events in the original, but sometimes the connections are not completely explicit. Sometimes prequels play on the audience's knowledge of what will happen next, using deliberate references to create dramatic irony.