Just as Inside Out goes deep into the brain of an 11-year-old girl, we're about to go deep into the background of Pixar's latest and, some say, greatest adventure. Inside Out is the result of five years of careful labor under sometimes difficult circumstances. Various story ideas were tried and discarded or reworked and, due to troubles with its neighbour film, The Good Dinosaur, there hasn't been a Pixar film since 2013's Monsters University (and not a non-sequel since 2012's Brave). It was worth the wait; the movie shows all of the incredible, painstaking craftsmanship Pixar is known for. Despite the simple-seeming idea of figures that represent emotions, the five come across as fully realised people. Each of them is capable of the feelings represented by the others and more. Sadness isn't always sad just because she's "sadness," she's also sad because no one seems to believe she has anything useful to offer the group. And not only Joy, but the other three, especially Fear, feel deep satisfaction at a job well done. This sort of complexity is the result of careful planning, production, and plenty of rewriting. It's fascinating to look deeper into Pixar's process and discover how the movie was made, what didn't make the cut, and what secret treats the filmmakers hid in the margins Here are 20 amazing facts you can use to impress your friends and heighten your appreciation of this modern classic.