Here is why this works: Everyone knows (and throughout the film we are reminded) that our DNA is unique and that we leave traces of it everywhere. For the film's conceit to work, we have to be willing to believe that a meticulous enough person could brute-force their way into fooling the system into missing their billions upon billions of shed traces. To do such a thing seems like it would require an absurd array of devices, procedures, and luck. In compact prose, with relatively few words, this exposition not only sells us on the notion that it could be done, but suspends our disbelief by credibly suggesting that it's done OFTEN ENOUGH that the setting's culture even has slang words for it. I wonder just how powerful slang might be as a worldbuilding device. There's a powerful social pull to slang, and as soon as someone hears it, they tend to entwine it into their waking consciousness very solidly so they don't miss future references to it. Imagine what you would think of a person today who didn't know what a Red State or a Blue State was. They'd seem beyond mere out-of-touch shyness, and would evoke a sense of severe reclusion, utter hermitry. Incorporate slang into your built world, and the reader is drawn in, immersed, because of the way their social mind naturally works. It's the difference between a Muggle and a Mudblood.

Just to pick nits here, because I think so many of the people who read this blog are at the level where picking nits can benefit, but it's not just slang, but jargon, too - perhaps more so - that makes this feat believable. Yet we are not jargoned to death. Reminds me of how fine the line between good exposition and bad exposition can be. By giving us just enough, the writer trusts us to infer the rest, fill in the gaps. We are in good hands here and not talked down to, and that's important.

Michael, that is a great insight, specifically your point about slang, how its use suggests the concept behind the slang is so commonplace, the slang for it has evolved into being, and therefore we -- as readers -- should feel comfortable that it just works in the context of the story universe. By the way, I know there are a bunch of slang dictionaries online, but one of my prized references books is my battered old version of "The Thesaurus of Slang" by Esther Lewin & Albert E. Lewin. in which it reverses the process: Instead of us looking up a slang word to read its definition, it lets the user look up a normal word, then suggests all sorts of slang references. It's an amazing tool. Thanks for the comment. That's a keeper!

Scott, I definitely want to check out that book -- thanks for the tip. And Annika, well observed -- jargon definitely fits the bill. Heck, Star Trek with its dilithium crystals and positronic matries showed just how far you can push jargon in service of a plot. (Though there were times when they probably ought to have dialed it back a bit!) :)

Every comment is so great. Kudos.I love this scene even though the voice-over is, as far as I could tell, not original to the script. Ultra Violet did a terrible job with a voice-over about a similar segment of societal outcasts. I love that in this exposition Jerome is actually telling us the world he lives in doesn't think he has the right to exist. So he has to literally create his own existence. Great exposition, to me, gives character first. Gattaca has that in spades.