In “Making Movies,” Lumet bluntly punctures the notion of “movie magic.” This is how the sausage gets made. As is the case on most films, Lumet shot piecemeal and out of continuity. “We went around the [deliberation room] three times: once for normal light, a second time for the rain clouds gathering, which changed the quality of the light coming from the outside, and the third time when the overhead lights were turned on. [Lee J. Cobb] arguing with Henry Fonda would obviously have shots of Fonda (against wall C) and shots of Cobb (against wall A).”

Simple enough, right? Not when your heavyweight actors — Cobb had originated the role of Willy Loman in Arthur Miller’s “Death of a Salesman,” while Henry Fonda was, y’know, Henry Fonda — are shot a week apart.

“But that’s where rehearsals were invaluable,” said Lumet, describing the hectic schedule:

“After two weeks of rehearsal, I had a complete graph in my head of where I wanted each level of emotion in the movie to be. We finished in nineteen days (a day under schedule) and were $1,000 under budget. Tom Landry said it: It’s all in the preparation. I hate the Dallas Cowboys, and I’m not too crazy about him and his short-brimmed hat. But he hit the nail on the head. It is in the preparation. Do mountains of preparation kill spontaneity? Absolutely not. I’ve found that it’s just the opposite. When you know what you’re doing, you feel much freer to improvise.”