Long before you sit down in a theater, and before a director yells "that's a wrap" on a film's set, a screenwriter painstakingly arranges thousands of words into a screenplay — the lifeblood of what you'll eventually see on the screen.

Dustin Lance Black, the wordsmith behind mainstream biographical films Milk and J. Edgar, just opened up about his screenwriting process in a fascinating video (above) produced by the Academy of Motion Pictures Arts and Sciences.

Black details his research tactics and writing techniques in memorable turns of phrase — for example, "land of lost scenes," discarded notecards that contain what he calls "my precious little children I've had to kill."

As for cards that make the cut, Black moves their scribbled contents into a "vomit draft," a typed screenplay he says he can quickly regurgitate onto his computer, since most scenes are now etched into his memory at this point.

Dustin Lance Black hovers over his screenplay notecards. Image: the Academy of Motion Pictures Arts and Sciences

"There's a terrible studio note, which is like, 'Just make [your characters] relatable'," Black, 39, says in the clip. "You know what, no, make them really them and really specifically them and it becomes very universal and that comes from research."

Black's "Creative Spark" video is part of the academy's documentary-style online video series "Academy Originals," which examines the process of filmmaking. A previous "Creative Spark" episode highlighted screenwriter Tina Gordon Chism (Drumline and Peeples):

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