This narrative trick is formally called in media res, meaning 'in the middle of things'. Pretty much the monkey wrench of the the Western Lit toolbox.

Ah-ha, an official title for this trick! Now I won't have to sound like some giant nerd when I try to explain this at fancy dinner parties. Thanks, man.

Hey Rob - great post. I learned something valuable here. What comes to mind immediately are James Bond movies. More often than not they open with a little 4 or 5 minute pre-credits action sequence - lots of fists, guns, explosions, and usually some kind of a chase. And a lot of the time the sequence isn't related to anything else in the movie, after the credits and the song! But it sure does get you in the mood for 007, now doesn't it? Thanks. John A