Zootopia has proven to be one of the biggest surprises of the year so far. Not only is it the best reviewed movie of 2016, it has also become one of Disney’s biggest box office hits of all time, earning nearly $800 million worldwide to date. Now, a new documentary on the making of the animated hit has emerged online, chronicling the early years of development, the wish of the filmmakers to make another talking animal movie in the style of Robin Hood, the abandoned plot involving a place called “Savage City,” and giving the film the “very real themes” of prejudice and bias (it’s also full of spoilers, so seeing Zootopia before you watch this is recommended).