Stories are not about plots or places. They are about people. Your readers don't actually care about that spooky old house on the hill until you put the mysterious Mrs.Fillibuster on the front porch every evening precisely at seven pm. The writer's development of memorable characters is crucial to the success of every story an author tells. What eventually happens to those characters is secondary.
As writers, we've heard that most great stories are about "ordinary people in extraordinary circumstances." There's one more critical element to that observation: our readers MUST care about those 'ordinary' people, or they won't bother reading to the final page. We can argue the merits of various plot devices all day long, but a stellar plot can be destroyed by poorly-drawn protagonists. On the other hand, a spectacular character can shoulder a shallow plot with aplomb.
How can you make your readers care about your characters?
Blood and conflicts:
One common prescription is to "make your characters bleed." This need not be taken literally. There are many ways your characters can shed blood metaphorically. However, it's worth noting how often successful authors place their protagonists in serious jeopardy, physically or emotionally. This directive is often also stated as, "good stories = characters + conflict," for those who like equations.
Don't confuse individual conflict with overall plot. Many conflicts are internal, as in: "man, that guy is really conflicted!" Recurring examples include characters who suffer alcoholism, fear of aging; or were spurned by love, smothered by momma, abused by daddy, ignored by a lover,unappreciated by the boss, dismissed by society, motivated by greed or lust, and many more. A popular "conflicted" character in many murder mysteries is the sociopathic antagonist - a "bad guy" who feels no conflicts overtly: no guilt, no moral quandaries, no remorse.
Each of us, as readers, finds ourselves able to identify with characters who experience emotional difficulties that are familiar from our own lives.
A pound of flesh:
The other critical key is to "lift your characters off the page." Two-dimensional characters are for comic strips, not for powerful stories. You may have heard this described as 'fleshing out' your characters. Inexperienced writers often try to provide detailed descriptions of each person introduced in a tale. We've all seen something like this:
"She was a tall, willowy blond, wearing a skin-tight satin sheath. Under a broad forehead, her green eyes dominated a regal nose, over pouting plum-colored lips..." You get the drift.
Better writers dribble out details about appearance on a need-to-know basis. They "show, don't tell" by using actions and reactions to carefully implant an image of each important character in the reader's mind. Your protagonist's movements reveal a great deal and, sometimes, can paint an entire portrait in one brush-stroke. Here's an example, from a recent single by country artist Brad Paisley:
"And then he nudged my arm, like old men do..." The only other detail we have about this fellow is that "he sat down in his overalls" on a bench at the mall. [Quoted from "Waitin' On A Woman" Time Well Wasted, 2005] Would you be the least surprised to learn that veteran actor Andy Griffith played this character in the music video? (By the way, country songs are stories, too - many of them offer writers amazing examples of how to develop characters quickly with a minimum of words.)
Live by your words:
Every word your characters utter offers insight. The best dialog needs nothing more than the occasional "he said" or "she replied" for clarity. Writers are admonished to "write the way you speak." Nowhere is this more crucial than in dialog. Just as an impersonator "becomes" his chosen subject, an author must climb inside the minds of his characters so that no false notes disrupt their voices. At the same time, each character will reveal his personality in conversations.
Consider these examples, and see how much is revealed in a sentence or two:
"I'm sorry, but this meeting is over. Excuse me. I have to get out of here...This is wrong." [Alex Cross in "Big Bad Wolf" by James Patterson, 2003]
"That's why he's helping, isn't it? This is not one MP to another. This is a bureaucracy trying to control the situation...This is someone deciding to feed us stuff privately so we don't go blundering about..." [Jack Reacher in "The Hard Way" by Lee Child, 2006]
"Maybe...hell, probably not. But I'd like a snip. I'll talk to a judge, send the paper." [Lucas Davenport in "Invisible Prey" by John Sandford, 2007]
Try to let your dialog flow naturally, as if you are merely taking notes while eavesdropping on your characters' conversations. Be wary of relying on dialect to illustrate your fictional creations. Part of the magic of great dialog is that it never trips up your readers; more than a smidgen of oddball words becomes a distraction. Consider this simple device:
"'Watch yer step there, buddy. I could've killed you by mistake.' He mashed his words together, saying "watcher" and "killja" and never unclenched his teeth when he spoke." Notice that only one word is altered, while the rest is offered as an aside. The dialog remains highly readable, and the audience can imagine this character's voice for themselves.
Why create serial characters?
Many best-selling authors achieve their greatest success by creating serial characters. There are several good business reasons for doing so, but for readers the reward is characters who no longer feel fictional. We come to know these protagonists so well that we anticipate their actions and words. We watch them age. We worry about them when they're in trouble, and we rejoice when they succeed. We know these people well enough to want good things to happen to them.
Convince your readers that your characters are real persons, not life-size cardboard cut-outs. Reveal your protagonist's deepest fears. Show us their tiny foibles and use gestures to paint vivid portraits without extraneous detail. Let your characters' voices unfold the story. If you've done your job, when your characters cry your readers will reach for a tissue.