Many works derive their gimmick from an unusual job that the main character or characters have. Perhaps it's a job that would be impossible in Real Life
, such as space-trucker or Defense Against the Dark Arts
. Or perhaps it's just a job most people aren't familiar with, such as firing people
But this gimmick usually isn't enough to drive a whole plot. Something has to go wrong at this job. An annoying client, a botched execution, a high-profile theft. But at the same time, since the job is so unusual, you want the audience to get a feel for how it works normally before you get to the main action where anything goes.
Hence this establishing trope. There are a few scenes at the beginning where the job is shown working normally. This usually comes at the expense of relevance to the main plot; the first job usually involves a client and characters that will not be seen later, though of course this could be the source of a twist later on.
Often it's just one job gone normally, and then the job that drives the main plot. Occasionally we'll see several instances of normal jobs, perhaps interspersed with character development, before the main action begins.
- In Sneakers, we see the crew at their job testing the security of a bank before having to steal the box that drives the main plot.
- In Paycheck, we see one instance of Jennings's reverse-engineering-with-memory-erasing job gone normally, before the big one hits.
- In Minority Report, we see some normal Pre-Crime arrests before Anderton is accused himself.
- In Equilibrium we see Preston doing his job of arresting sense-offenders normally before he goes off his Prozium and becomes one himself.
- In Looper we see several of the time-travel killings gone right before the main action.
- In Up in the Air we see how Bingham's job of firing people works before various factors upset his comfort zone, starting with changes to travel policy.