The Dark Crystal has always been Jim Henson's creepiest movie, but when it was finally released it was considerably toned down from his and Frank Oz's original vision. YouTube user scoodidabop has spent years re-editing the film, using Henson's original notes and various deleted scenes to create a far, far creepier movie than what you remember.
The removal of the narration and inner monologues is always a welcome change to any movie, but apparently the Skeksis were also not going to speak English (except rarely). You think the Skeksis were disturbing before? Check out what they're like when you don't understand what they're saying. Shudder.