"To say that the Final Fantasy series, running since 1987, is popular, is a bit of an understatement. The series has reportedly sold over 97 million units worldwide, and has dozens of video-game, movie, comic, and book tie-ins. The main (numbered) series reached fourteen last year with the release of the MMO Final Fantasy XIV, which had a lukewarm reception. The Final Fantasy series is interesting in that each "volume" doesn't relate to the previous game: each entry takes place in a new world, generally fantasy or science-fantasy, with new characters and a new plot. The only exceptions to this rule are 2003's Final Fantasy X-2, a direct sequel to Final Fantasy X, and upcoming Final Fantasy XIII-2, a direct sequel to Final Fantasy XIII."