Sure, you get the first story, and you fall in love with it. You like the characters, you like the storyline, you like the twists and turns...and when the story is over, you're left feeling satisfied by the journey the writer has taken you on from the first page to the last.

But, as many writing teachers will tell you, there is a HUGE difference between 'story' and 'plot'. Plot is only used for this one particular story at this particular time. The story, however, reaches out in all directions, taking place both before AND after the story you've read has come to an end. For example, Harry Potter is not the only student at Hogwarts. The plot is the problem solved in each book, surrounding him and his friends. The 'story'...could come from anywhere. The other students all have stories of their own. The teachers have stories of their own. The school itself has a history and a future. So, looking at it from all different angles, a number of spin-offs could keep that Harry Potter 'mythology' going on forever. Same with "James Bond", or "The Matrix", or "Lord Of The Rings", "X-Men", "Bladerunner", "Sin City", "War Of The Worlds"...the possibilities for new angles and new perspectives are virtually limitless. You could tell brand new stories from a completely different point of view, and breathe new life into a story that's already been told.

But do 'spin-off' stories really get attention? Do you really 'LIKE' them? I mean, they're not the same characters or storyline that you fell in love with in the first place. Are they seen as cheap knock offs of a bigger story? Or are they a way to get more depth and perspective out of a story that could be even bigger if given a whole new meaning from a different side of the legend? (Telling 'Darth Vader's' story as a prequel to the original "Star Wars" trilogy, for example) What do you think? Are spin-off's your thing? Or would you rather just have good stories left alone?

Think of it thie way: how many movie sequels do not suck. [for that matter, How many prequels do not suck].

The number is very, very low.

Unless you plan on doing a trilogy like the LotR or X-men, resist the urge.

The classic Starship Troopers was a decent movie. The author did nothing further with it. Hollywood decided it needed sequels and they sucked raw sewage. The SST sequels were horrible because they were cheap, weren't written by a master and were simply made to cash in on a name that the studios were renting. They were in fact so bad that they should be burned and not inflicted on unsuspecting eyes.

I generally don't write a second story in the same universe as an earlier one. There are a few exceptions to that rule, but unless I'm happy that I have an idea that is at least as good as the original, I won't even start. A poor second story will drag down the original, and I don't want that.

When it's done well, though, it can be great. But I don't know of how many print authors I've read who have fallen into this trap. The first few stories may be fine, but so many fall down and seem to be writing in that universe because they've made money from it in the past -- the stories just don't have the spark of the original(s). I would hate to fall into that same mistake.