"Do you have any idea what it's like to have done things you can never forgive yourself for?"
"Lamont. Whoever you were - whatever you did - it's in the past."
"Not for me, Margo. Never for me."
So, you've begun in medias res, the story's clipping along at a brisk pace, and you've got a ripping good tale in the offing. The only pest in your Potage Parmentier is the past. It's refusing to stay past. It wants to be present, and it's being obnoxious about it.
For many writers, this is a right pain in the arse. We've suffered through novels where the author keeps stopping the story to yap about what happened ages ago. We've sworn never to allow that sort of thing in our work, by gods. If history has got to come into it, we'll keep it short and snappy. We'll make it matter.
That's really easy to say. Extremely hard to do. Take it from one who has seventeen thousand years of backstory to deal with, this is one of the hardest things about writing. Working all that stuff in without killing the pace of the story is bloody difficult. Choosing which bits to include and which bits can be safely left out is even worse. There have been times when I've wanted to sob at my computer when I've realized that yet again, what happened in the distant past is having an atomic impact on the present, and that I've already got fifteen chapters liberally salted with ancient history, and that I'm going to have to cut down on it but none of those bits want to be cut...
However, I must be doing something right, because I've never yet had a reader come up and complain about it. In point of fact, they've been rather pleased with finding out all of that nifty stuff that happened a long time ago. They never seem to have felt that the past was encumbering the present, but enhancing it. This has been the case with both friends and mere unfortunate acquaintences who made the mistake of wanting to have a look at some of my work. So I'll share with you my not-so-secret secrets.
WHY THE PAST MATTERS
I have to confess to a certain squishiness when it comes to the past. I love history. I love history so much that I very nearly became a history major, and that's probably why I'm so apt to go into lavish detail on the histories of my worlds and characters. I think this stuff really matters. We're all haunted by history, entranced by it, ruined by it, compelled by it. If you don't believe me, just remember the last time you traced a really strange personal quirk back to your childhood. Look at the fact that what we believe in was, in many cases, handed to us by people who died a very long time ago. New civilizations are built on the ruins of the old. Past matters matter.
And they will matter in your writing, to a greater or lesser degree. Granted, there are plenty of successful novels out there where there seems to be no past at all. The characters spring up fully formed on page 1, and what happened to them at age 9 never comes into it. For all we know, they didn't have a yesterday. Neither did their world. And the story gets along just fine without. But there's a certain thinness. We've splashed around on a water slide and had a great time, but it's nothing compared to the ocean, is it? Things are the way they are, no explanation, and it all seems somewhat artificial.
But it's worse when an author throws in a chunk of the past as a lame attempt to add depth. You know what I mean. You find out on page 47 that the P.I. has taken this hopeless case and will put himself into harm's way for no pay because the client is being victimized by the man who killed his wife fifteen years ago. The bomb gets dropped and bombs. The story isn't changed by it except to become cliche. Yawn.
That's not a past, it's a contrivance. And we're not talking anything contrived in our stories. Oh, no. We're talking about a past that is so fundamental to the story that nothing makes sense without it. A past that really matters. Pasts that:
1. Ensure the readers don't get the impression that the characters and the world they move in exist only for the author's nefarious purposes. Giving bits of the pasts expands the story, allowing it to extend before the beginning and live beyond the ending. This is good for several reasons: it makes the story feel more real and also keeps the reader speculating about what came before and might come after. Prequels and sequels, anyone?
2. Give information vital to the story. In Robert Jordan's novels, you can't know why it's such a horrifying thing to be the Dragon Reborn unless you know that the original Dragon went mad, broke the world, and murdered everyone he loved. And this knowledge gives you fear for what might happen next. Without it, the Wheel of Time would have been another good vs. evil yawn. Which leads very nicely to
3. Increase tension, heighten anticipation. "History repeats itself," anyone? This happened before and failed miserably, or succeeded beyond our wildest dreams - too bad it was the enemy succeeding... Old lovers rediscovering each other is old hat, but not so much when they have secrets that the readers know and are afraid will get out.
4. Help us make sense of why the characters are who they are, and why things are the way they are. I'll take a page from my own books, here. Sovaal's initial hatred of Dusty would seem pretty irrational if one didn't know that she reminded him of Kalsenah ne'Shadah, who not only spent the better part of hundreds of lifetimes getting further up his nose than an alien implant, but very nearly destroyed the Universe. And that's not all by half...
5. Deepen the impact of everything; change assumptions and attitudes. More pages from my books, I'm afraid. I used the past to this effect with Adrian, my wonderful antihero, and it worked a dream. Somehow, finding out he almost became an art history professor instead of an assassin really changed readers' perceptions of him. And making sure that readers knew how much the people he'd killed had mattered to those left behind made it much harder for readers to fall for his charm. Do you know why a million deaths are a statistic? It's because there's no history in them.
6. Create the present and impact the future. This may play out to a greater or lesser degree in your story, but it's a fact that things are as they are now because of what happened before, and that those past events will have some effect on the future. It could be as simple as your female lawyer choosing to practice law because she was molested as a child, becoming a defense attorney for a high-powered firm because it paid more than the prosecutor's office, and now has to defend a molester. It could be as complex as a series of events that began with the death of a prior Universe and follows a great unfolding sequence until everything that has come before has led to now, and means that there may soon be no future. Either way, a chain of causation can be followed to the present moment and used to get a glimpse of what might happen next, if things don't change.
So you see, the past matters greatly. But you can't just stop the story to explain, "Oh, yeah - you know, like all this stuff happened, and it was kinda like this, and this is what everybody thought, and blah blah blah we now resume our regularly scheduled story."
What to do?
THE SUBTLE ART OF MAKING THE PAST PRESENT
First we're going to talk about when it's appropriate to work the past into the present, and then we'll get into the actual mechanics of it.
Get the present going first. Generally, you'll want to get the story off and running before you drop in a history lesson. I've seen some successful books that flash back immediately, but most of the time you should avoid starting out with your character getting all misty-eyed in the second paragraph, or stopping in the middle of the explosive opening scene to recall how he became a commando. Let the readers get settled in before you go into all that.
Wait for the opportune moment. You can't just drop the past in any old how. You should wait until it becomes vital to the current story - whether it's because it impacts the plot, the characters, the meaning of all the story's events, the course of its future, or otherwise.
Whet the reader's appetite. Drop some intriguing hints, build it up, hint at something explosive before you tell all. A past they've been begging you to reveal is going to go over much better than one you've just sprung on them with the sudden "By the way, there's something you should know"prelude.
Use props. A memento, a ruin, a monument, something tangible can be a fantastic springboard. It's something in the present that physically connects us to the past, and it's powerful.
Juxtapose things. This sea becomes that, this conversation recalls another, this situation mirrors the long ago.... You can juxtapose nearly anything, and they can be very similar or really not similar at all, as long as they evoke the past for the character recalling it.
In general, avoid going back when you should be going forward. Don't dwell too much on the past when things in the present are at their boiling point. The middle of the screaming match is no time to break off for a flashback to previous arguments. If the past has to come in, let it become part of the action. Let the characters scream it at each other. Think "oh, shit, here we go again." Freeze up, break out in shakes, react much more strongly than they would have without the burden of the past. Whatever you do, though, in the middle of the action, keep the past short, sweet and to the point.
Choose the bits that really matter. The more it affects the characters or their situation, the more important it becomes to the reader. If it's there for mere curiosity value, because it's interesting to you, but doesn't really have any bearing on what's going on, it probably needs to be ushered firmly off the stage. Snappy lines that reference characters' history together serve the great good purpose of giving the impression that they have lives outside the limelight, and quick references to interesting factoids about your world's history solidify its existence in the readers' mind, of course. But keep those somewhat limited unless they have a greater importance. And in general, follow the rule that the longer it is, the more meaning it's got to have.
Choose the bits with intense emotional impact. That impact can be subtle or in-your-face, but it should be there. Use the stuff that evokes a strong reaction that fits with the direction you're taking the story in. I know that, as a reader, I'll generally tolerate a lot of backstory all in one place if it's extremely funny, shocking, interesting, saddening, angering, uplifting, or otherwise makes me sit up and go "Wow."
Things should change. Finally, after you've dropped in your bit o' history, the story should be different for it. It can be as simple as helping the character's mood change, or as complex as changing the readers' entire perception of things from page 1. I'm not advocating you subject every tidbit independently to that test, because some bits are meant to be built into a byte. But everything you include should, independently or taken in toto, lead to change.
That comes pretty close to covering the what. Now we need to address the how.
1. The offhand comment. I say "offhand," but often it's very purposeful. This can be a sentence or two of dialogue or narrative. The main thing is, it's very short, and may stand alone or serve as the hook to a more in-depth exploration. When you're planting seeds for future past-plumbing, you're very often going to use the offhand comment. You'll also use it when wanting to get across that characters have known each other, or known of each other, or that the world has been around for more than ten pages.
2. Character interaction. Here, it's mostly dialogue. People may talk about their past together, their past before they met each other, how things sure aren't like they used to be around here, a funny thing happened in this part of the country, do you remember when that mountain went boom, or anything else. Just make sure you avoid the fatal error of having two people with a shared history discuss that history like neither one of them experienced it together.
This technique can also take the form of showing somebody around the place.
3. Interior monologue. Spying on thoughts, in other words. You don't want to let your characters navel-gaze for too long, but do let readers see your characters thinking about things. It saves them having to talk to the cat when they're alone.
4. Dreams. Don't shudder. They can be useful when they're done right and sparingly. The dream may contain fragments of the past, or a surreal tapestry of bizarre events that lead the character to remembering something they needed to recall. Some dreams may even lead them to see the past in a new light.
5. Narrative. This is the easy-breezy version of sharing the past: just relating it. It can take the form of the character informing the reader (directly or indirectly), or if you've got the freedom of a more loose third person point of view, the author or narrator letting the reader know what went on. Keep this fairly limited. No more than a few paragraphs: don't go on for pages and pages. If you need to do that, then you need (drumroll please):
6. Flashback. This is the technique to use when you really need to get in-depth, when you need to go on for several pages, or when you've got a bit of the past so juicy that it just begs to be dramatized. Caveat: don't abuse this technique. Only use it when you really, really need it. Otherwise, you'll be tempted to flashback every time a bit of the past needs to be brought into the present. You can only have so many flashbacks before the reader decides that your next book signing would be the opportune time to throw your magnum opus at your head.
So there you are. There's enough contained herein to give you a good, solid foundation to build the past into the present on.
Now I know you're going to ask, how much of the past should I put in there? Tough question, and it can only be answered with the vaguest of rules: as often as necessary. If you're writing a book where the past is nearly as important as the present and has a deep and dramatic impact on the story's end, then you'll include quite a bit. If it's only nominally important and your story lives mostly in the present, you'll put in less. Your story will probably tell you what it needs. If not, your test readers can help you figure out whether you've got too much or too little.
Also keep in mind that a short story will tolerate a lot less reminiscing than a novel.
Now, with all that in mind, go make the past present.