As far as DVD and Blu-ray extras go, director's commentaries are right up there with the deleted scenes and bloopers reel. When done right, these audio gems are insightful, funny and loaded with mind-blowing trivia.
Not convinced? Try listening to a hyperactive Quentin Tarantino talking you through True Romance without geeking out when he throws factoid after factoid your way.
From references nobody picked up on, to behind-the-scenes madness, here are the movie secrets that came straight from the horse's mouth...
10. Kong: Skull Island Was Inspired By... Pokemon!?
Kong: Skull Island is a stylish offering that wears many of its influences proudly on its sleeve. There are some nice call-backs to the 1933 original and those Apocalypse Now references were rather obvious.
Director Jordan Vogt-Roberts, however, drew on more sources of inspiration than you might think when he brought the giant ape back to the big screen, and he candidly lists them all in his audio commentary.
Among them are Metal Gear Solid, Full Metal Jacket, Oldboy, The Host, Cannibal Holocaust, Spirited Away and... Pokemon?
You might be wondering what a Nintendo game full of collectable critters has to do with King Kong, but once the parallel has been flagged up, it can't be unseen.
Those terrifying Skull Crawlers that Kong battles in the movie were based on none other than Pokemon's Cubone, a creature which wears the skull of its dead mother as a helmet... wait a second, that was in a Nintendo game?