I first saw The Sandman as part of an animation festival. Paul Berry, the animator, would later go on to work on The Nightmare Before Christmas and James & the Giant Peach, but passed on in 2001 at the too-young age of 40. This is his masterpiece, based on the story "Der Sandmann" by E.T.A. Hoffmann.
The less you know going in the better, so I'll just let it play now. Make sure and watch it through the closing credits. Unless you're scared. Buck buck buck-kaw!