In the writing class I’m taking, we’ve work-shopped a couple of stories that revolve around a character suddenly remember something of significance that happened to her in the past.
Here's generally how it unfolds: the story is told from the present day/now, with the character doing something languid--like sitting in bed wrapped up in quilt, remembering. As the story continues, we move back and forth between the present day action and the traumatic event being recalled. In the present tense of the story, the writer describes the character doing mundane things, like spreading butter on a piece of toast or pouring over her reflection in an antique mirror. These activities trigger additional memories that reveal for the reader more of the traumatic event. By the finish, the event is explained---the baby burned in a fire left by the mother's drunkenly dropped cigarette; the car skidded off the road and into an oncoming semi, the aliens sucked up all of the townspeople, except for those with ginger-colored hair (ah-ha, we think! That's why the writer spent two pages having the character stare at the split ends of her red hair, braiding and re-braiding the strands as she did so). The end scene is usually a return to the opening, with the character having moved glacially over the course of the day from the bed to the toaster to the bathtub, and back into bed again.
What is wrong with this approach? Isn't the rule of fiction that something of significance happens? Something happened, yes. But that big something occurred in the past.
One might argue that a memory can create change. Yes, that’s true, though it is the most passive way to alter your character, in large part because it occurs internally rather than out in the world. However, the change that it creates needs to be significant (i.e. not a change from white bread to eating whole grain).
Let’s just say that you’ve decided that your character is paralyzed with grief or guilt. That’s fine, but it's not enough to write a story that shows us the cause, you must then show us the possibility that the paralysis will either get better, or get worse, as a result of remembering what happened.
Here, we face another problem with this type of story approach--it's very, very hard to have a character experience a change simply through the act of remembering. We have got to get them out of their own heads--we need to see them out in the world, interacting with other people, yelling at old ladies, running for the bus that's pulling away from the curb--unless we see them moving through space and encountering others, we have very little evidence of who they are. Sticking the character in a room thinking is death to the writer, because it traps you. Why limit yourself to one room to tell the story when you have the whole of the world to work with?
Now, don't get me wrong. You can have a remembered moment create change. It's fine if during the course of the day the man whose father murdered his mother begins to see things that remind him of an act he's trying to forget. Perhaps the bus driver's face looks much like that of the policeman who came to the house. Perhaps the smell of gasoline from the exhaust triggers a memory of lighter fluid. As long as the character is in the act of discovery in the present moment, we're headed in the right direction, because that discovery will lead to some kind of greater realization--and that realization can tip one of two ways---it will make the situation better, or it will make the situation worse. In short fiction, you don't have a lot of time to do much else.
But let me make one more plea against the dramatic flashback. The more dire the memory is, the more it will undermine the present tense of the story. How could it not? You really want your most dramatic action to happen in the present day of the story. Otherwise, you run up against a bunch of other questions from the reader. Why is he just remembering this now? Why has she not thought of this before? So, my final word of advice is: if you want to write a story about the house burning down, consider just dealing with that moment--not with the moment ten years in the future where the character suddenly remembers, Oh, my, God, the house burned down. How could I have forgotten? More than anything, use flashbacks sparingly, to reveal only what is necessary for us to understand what the character is going through now, right at this very moment. That's what we're most interested in.