Far Flungers
When it comes to "Making of" documentaries, I put one above all others. It is "Hearts of Darkness: A Filmmaker's Apocalypse" (1991), a full-length feature about the filming of Francis Coppola's "Apocalypse Now". Nothing quite illustrates its impact like Francois Truffaut's statement: "I demand that a film express either the joy of making cinema or the agony of making cinema. I am not interested in anything in between." That the pain it captures eventually translated into cinematic greatness only serves to make it more compelling.
May contain spoilers