The Incting Incident and then the... um, Inciting Incident

In Syd Field they're plot points but I think there's a fair bit of crossover with the inciting incident.

The inciting incident radically upsets the balance of forces in the protagonist's life. -- McKee, Story

-- and typical examples of these are things like the shark eating a girl in Jaws (and her washing up on the beach) or Luke discovering that his parents have been killed by imperial stormtroopers.

Part of the idea is that in the first part of the film or story you get to see the world as it usually is -- see the characters with their ordinary problems -- then, after the inciting incident, the various crises throw all that out of balance (though it'll often tie back into the characters' original problems.

But I've noticed that for most of my screenplays the thing that throws the world out of balance really occurs in the first 5-10 pages. The characters typically won't realize it until a bit later, after we've had time to meet them. But the threat is already in motion.

Many films do this actually. For instance, both Terminator 1 and 2 -- the Terminators show up in the first scene then we get to see them slowly track their way to the protagonist.

Of course, one reason I do this is because I'm rather paranoid of boring whoever's slogging through the stack of spec scripts mine happens to be in. I'd like to pique their interest early so that hopefully they'll at least remember the character names by the time they get to act 2.

I wonder if the modern trend where writers have to break in via spec scripts is part of the reason we see more punched up first acts as opposed to spacious introductions.