It's reasonable to assess that most "making-of" movie documentaries aren't much more than trivial, mildly entertaining fluff pieces intended to bulk out the home video release with extra "content" and not much more.
But on that rarest of occasions, a behind-the-scenes documentary itself can turn out a more engaging and well-wrought piece of film than the work of cinema it's actually covering.
That's absolutely the case with these 10 documentaries about the filmmaking process, all of which ultimately superseded the source project with their jaw-dropping observations of movies in crisis, sharp insights into the creative process, and even their unexpected ruminations on the human condition.
Each of these films told stories that surpassed those of the adjacent feature, ensuring they're not merely well-crafted companion pieces but essential documentaries in their own right, no matter what you make of the film on which they're based.
And no, Hearts of Darkness: A Filmmaker's Apocalypse didn't make this list, because as excellent as it is, it still doesn't manage to eclipse the achievements of Apocalypse Now itself...
10. Crystal Lake Memories: The Complete History Of Friday The 13th
As iconic as the original Friday the 13th might be, it's tough to call it a genuinely good movie, no matter its entertaining gore and delicious final twist. The majority of the sequels, meanwhile, range from passable, to dull, to unintentionally hilarious, to...whatever Jason X is.
But decidedly more entertaining than any single film in the franchise is Daniel Farrands' Crystal Lake Memories, a ludicrously comprehensive 400-minute (!) documentary about the entire series.
For any fan of Friday the 13th, Crystal Lake Memories is both insanely enjoyable and extremely informative, largely thanks to the exhaustive access Farrands has been granted to the cast and crew members of every single film - the notable exceptions being Kevin Bacon and Crispin Glover.
Far more than a glorified series of behind-the-scenes featurettes stapled together, Farrands' film crams a frankly obscene amount of fascinating content into its epic, near-7-hour runtime, and smartly refuses to shy away from the franchise's less-dignified moments.
Also be sure to check out Farrands' prior documentary about the Elm Street franchise, Never Sleep Again: The Elm Street Legacy, though unlike Crystal Lake Memories it's not decisively better than all the movies it's covering.