Found while cleaning: My last Men in Black outline, in the form of a letter to Barry Sonnenfeld, from mid-way through the (arduous) 4 yr process. (Purple scrawl is Barry's notes in my writing.) I'd just been been rehired - after having been fired for the 1st (but not last!) time. 
Creatively it was a joy, & the film was one of those rare things: a ton of super talented people working at their prime, all of whom elevated the script beyond what I (literally) could have imagined. But the process itself was tough - for a lot of reasons, many of my own making.
And I learned a TON during it, including the importance of perseverance & flexibility - & patience. I also learned (through failing, to be honest) how to take notes, & how to use the notes to not just make the script better but to actually become a better writer (and person).
This outline came after I'd done about 10 drafts (some w entirely different plots!), been fired for a draft or two, then rehired for another 10 drafts. I made a ton of great friends on it - & (sadly) a couple of the opposite. But I'm so glad I stuck with it & saw it through.
The 1st plot (which had a similar STORY) got Steven Spielberg involved, & then Barry Sonnenfeld, then Tommy Lee Jones & Will Smith.. but Barry wanted to set it in Manhattan, which was a great idea, so we set my script - which took place all over the country - in NYC, and revised.
It was funny: in my first meeting w Barry, we screened The French Connection - & he said "Just like The French Connection, but with aliens." Barry felt (correctly) that NYC was more rife with people (esp then) that you'd think were essentially aliens living under human cover.
In my first meeting with Tommy, he said "It's either science fiction or comedy, make up your mind*." I told him it wasn't good enough science fiction to be drama. I felt it needed the kind of leaps of faith one takes when the mood is more comic. To me, the mood was everything.
(*He *may* have added an expletive after "make up your mind...") :)
Two weeks into the movie Barry said to me “Tommy just figured out he’s in a comedy.” I think part of the reason he’s so good in the first one (and I think he’s great) is that he played it so straight.
