What makes a sequel a sequel? Well, the smart-ass response
is that it’s a story that comes after another one; you know, in sequence. But,
that obviously isn’t a sufficient definition. Every story involves a sequence
of events, so some of the events come after other ones. Chapters come after
chapters, “books” (as in the Lord of the Rings) come after “books”, but they
aren’t sequels in the sense that “Pirates of the Caribbean: Dead Man’s Chest”
or Karate Kid 2 are sequels.