A script is the blueprint for a movie or TV show. Except...
When you're just starting out, your breaking-in script isn't actually a blueprint. Your breaking-in script is actually a cover letter, designed to get you meetings and jobs.
After you've broken in and decided you're ready to create your own TV show or make your own film, your script still isn't a blueprint. It's now a fundraising letter you will use to raise the capital you need to actually make that movie or TV show.
Or, it's a recruitment letter for you to attract the collaborators who will help you raise that capital.
Once you sell that script or raise the necessary financing, your script still isn't a blueprint. For at least a little while, your script is now a kind of memo assuring — revision by revision — your well-moneyed investors that their capital is in good hands. It's where you show how you're making all the responsible budget cuts and adjustments. In modern Hollywood, it's proof of good corporate citizenship.
But at the same time, your script is also functioning as a memo assuring your creative collaborators that their talents are in good hands. It's where you show that your responsible budget cuts aren't sapping the life out of the script, or messing up a juicy role, or cutting out the scene that made someone commit to you in the first place. In the romanticized world of creatives, it's proof of artistic integrity.
Once you get a green light and start prep, your script still isn't a blueprint. During prep, your script is a tally of budgeting and scheduling dilemmas to solve. It's an inventory of problems for you and your team to tackle before filming can begin. That means it has to be clear, direct, accessible. And often, flexible.
Also, it goes without saying, during all of this, your script also needs to be art. It needs to be a font of inspiration and emotion and enchanting possibilities for you and your collaborators, pushing each of you to do your best work. Otherwise, everyone is fucked.
Once you start production and the cameras start rolling, now finally your script becomes a blueprint. For a TV show, that can be 7-8 days.
Then filming is over pretty quickly. And when you're cutting your footage together, your script is no longer a blueprint. In fact, in the cutting room, for all practical purposes, your script no longer exists.
One of the best pieces of advice I ever got was from James Mangold. He came into the editing room while I was trying to put a TV episode together and told me: "The script doesn't actually exist any more. The shooting experience doesn't exist any more. All you have now is the footage. It's your job to tell the best story you can with what you actually have in front of you."
It was great practical advice. I set the script aside and started telling the most gripping story I could with what I actually had.
What's my point in all of this? I don’t particularly give a shit one way or another what metaphors people use when regarding the role of a script. A script is a machine! A script is a north star! A script is an incontinent monkey riding on a kangaroo! Etc.
That said, I also don't think it helps an outsider’s case for them to write a detailed blueprint for a movie when they’re at the stage of their career where their script should be functioning as a hyper readable cover letter saying "look at me, great undiscovered writer here!"
I think it also means, if your script is at the stage where it's a recruiting letter for actors and actresses, then you need to make sure it functions as such. Now it can't just be a recruitment letter. Or be too desperate or obvious about being one. But practically speaking, it still needs to work like one. It needs to stand out to each potential collaborator, whispering into their ear at night, "this is the one you actually want to do."
Another solid piece of James Mangold advice. At a certain point of working on a script, I mentioned to him the quality of performer I was hoping to recruit for a role I'd written. Mangold asked me, quite plainly: "Can you point to the scene in the script that would make any of these performers you named actually want to chase after this role?"
I realized: I couldn't. I had all these grand plans for this character. But I wasn't going to recruit a great actor or actress with grand plans. I was going to attract them by offering a great character in great actual scenes that they would love to actually perform. I was hoping my script would function as a great recruiting letter without making sure it was actually functioning as such.
This might be the heart of my practical screenwriting philosophy: you have to know what practical goal your script is supposed to be accomplishing right now. That can be in terms of that script's life cycle and/or in terms of where you are in your career.
For me, once I recognize what my next pressing practical goal is, I try to step outside my intentions and look at my script objectively and ask: what can I do to make this script better accomplish this pressing practical goal? The trick here is not just maximizing the likelihood of accomplishing that goal. The trick is maximizing that likelihood without losing the inner connection that led me to writing the script in the first place and without losing the vision I have for what the script can ultimately bring about.
A great script shouldn't just function as a great blueprint for a great movie or TV show. It should also function as a great fundraising tool and a great recruitment letter, helping you marshal the resources you need to make that great movie or TV show in a risk-averse industry ever more reliant on sequels, prequels, and spinoffs. Ideally, it should also function as a great recommendation letter attesting to your untapped potential as a future staff writer or showrunner or writer-director or whatever other role or gig you're trying to write your way into.
You don't want to just write a great blueprint and then stand back and hope for the best. You want to write a great script that can get you through all of the well-manned gates that stand between where you are now and where you want to be: on set seeing your script being filmed. And that is when you stand back and just hope for the best.
This is like Mamet's three uses of the knife but... six or seven uses of the script.
It's amazing how easy it is to spend a ton of time as a writer thinking about why one's characters do what they do, what they want, what they're doing despite what they want, etc., without asking the same questions about ONESELF. I've read a lot of (the usual) screenwriting and playwriting books, and rarely do they treat the writer or the script as anything but matters of formal inquiry: what is the shape of a good script, what are the habits of good writers. Your posts here are the rare exception and, selfishly, I really hope you keep writing them, because:
Writing tends naturally to involve so much of the bad kind of self-awareness: "Do I suck? Why do I suck? Why am I such a lazy bastard?" What you're talking about here and elsewhere, by contrast, is a very healthy--because immediately useful and generative--sort of self-awareness: "What do I really want at this stage? What can I tweak to get there?" I don't think anything can remedy bad self-awareness better than crowding it out with the good kind.
I say this time and time again: it's a miracle any film or tv show even gets made.