It's no secret that sequels and series are a hit among readers these days.  Why? Because we want more.  Series novels give us more time to become invested.  It gives us more material to become attached to.  Generally, a win-win for readers and writers.

So, what do we want to see in a sequel?  What makes it powerful, without being redundant?  And why don't we want a book that's only an extension of the first?

As a rule of fiction, main characters are generally a little clueless in the first book.  If they had all the answers, the story wouldn't be as fun.  They have to learn something and struggle a little.  By the end of the book one, they've learned a little bit.  No one wants to read another book about clueless characters that still haven't learned a thing.  We don't want to see them make same mistakes again and again.
Obviously, there still needs to be conflict so they can't be a sudden know-it-all.
Exhibit A: Harry Potter  They grow (literally and figuratively, but still stay clueless enough to make mistakes.

Independent Story Arc
Cliffhangers are one thing.  Making me wait twelve months to reach the conflict or resolution of the first novel, not okay.  The thing about trilogies is that there are large conflicts and small conflicts.  Three tiny story arcs within one large story arc.  If we look at Twilight, it had three (four is arguable) books with their own (slightly weak) story arcs, and not much of a larger story arc.  People keep chasing them trying to kill them, basically.  ((Sorry to beat up on that series. I was a huge Twi-hard, but I needed an example)).
Exhibit B: The Lunar Chronicles, each novel, with its own story arc exists within one large story arc.

Something Old, Something New
I'll let you in on one of my biggest pet peeves…when everything I love about the first book is missing from the second book.  It makes me absolutely bonkers.  Sorry to beat up on another book, but The Daughter of Smoke and Bone was absolutely one of my favorites.  I could not put it down.  The conflict, the romance, the SETTING (it was Prague).  The cliffhanger.  Swoon.  But the sequel.  Ouch. Different setting, no romance, different story basically, and a completely different form of conflict.  Whoa, whoa, whoa.  What happened to the book I loved?  It literally took me so long to finish the second book, and I'll admit, I didn't even finish the last one.  I still feel bad about it.  The same thing happened with The Bronze Horseman's sequel.  It pains me so to even mention something I didn't love about that book.  It hurts.
Exhibit C: Throne of Glass.  It takes place in the same place, same character, but new romance, new conflict, new story.  Enough to make me happy and enough to make me interested.

Strong Characters
Let's face it, it's the characters we want.  Weak characters might not even get me through the first book, let alone pick up more.  And here's where Twilight redeems itself.  Hate on them as much as you want, but we all came back for the sparkly vampires.
There's that feeling we get when we pick up a sequel and we see the characters we love, and it just warms us.  
Exhibit D: Black Dagger Brotherhood.  Even if each book is about a new character, we still get to visit the old ones, and it feels like seeing old friends.

This sort of falls into the story arc category, but at the same time, it's something different.  I want to feel confident, as the reader, that the author knows where we are going. I want to know that there is direction and that he/she is not just making this up as he/she goes.  I hate to say it, but The Maze Runner did this to me.  As exciting as it was to follow along on that crazy adventure, it felt a little bit like the author had this crazy, awesome premise, but didn't exactly hash out the plan before he started writing.
Exhibit E: Outlander  She gave me confidence, from the very beginning, that the story was going to come back somehow.

You may have noticed by now that I am very critical of sequels.  It's rare for me to like a sequel as much as the first book.  But think about, if I'm picking up the second book then it must mean that I loved the original and it therefore, has large shoes to fill.  It's hard to make a worthy sequel (or series).  I get that.  It has to do so much more than the first one did, if you think about it.  But I think, if done right, the payoff is huge.

So, what do you think about sequels?  What do you love/hate about them?  Which ones are your favorites/least favorites?  What do you think it was that made you love/hate them?

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