I get a lot of resistance about my wrathful judgment of flashbacks.
Here’s the caveat.
Flashbacks are not the enemy. Unless they are lazy. Then they are the enemy. Like any other expositional scene that spoon feeds the reader information.
A good flashback is dramatic and illuminating, like the flashbacks in The Usual Suspects, to reveal misdirection, or in Harsh Times where the flashbacks to Afghanistan are strobing, intense, free of dialogue and violent, to reveal what the inside of Jim’s head looks like.
Flashbacks as setup mostly suck, and are 99% used for purposes of evil instead of good, which is a huge red flag to readers that the script is going to be a boring spoon-feeding in other ways.
The rule of thumb is, if your screenplay is about a bunch of old business that’s finally going to be settled, you don’t start by showing all that old business. You show, in dramatic conflict, that there is a bunch of old business, and make me wonder what the hell is going on.
Curiosity turns pages. Giving the answers away bludgeons curiosity to death.