Guillermo del Toro is one of the most imaginative directors working today. The stuff this guy comes up with is incredibly cool! Like any artist, when the director has an idea he needs to write it down or draw it out to bring it to life. I’m sure the guy has a ton of sketchbooks full of awesome stuff.
Thanks to the wonders of the internet you can now look at a few of his sketches from several of his films, such as Blade, Hellboy, Pan’s Labyrinth, Pacific Rim, The Devil’s Back Bone, and even glimpse at his vision of H.P. Lovecraft‘s At the Mountains of Madness, which will unfortunately never happen.