As much as I’d like to deploy a more current analogy in describing “The Dark Crystal,” I’ll revert to 1982, when it was released. This Jim Henson puppet fantasy is a dismal cross between Dungeons and Dragons and another popular board game, Risk. There are various clans that seem to be murky geopolitical metaphors (Fascists? Pacifists? Japanese-speaking, Irish-looking Greeks?) in a parable about the Cold War concept of mutual assured destruction. Most of the puppets are extremely creative but also extremely unattractive, as are most of the mock-Medieval settings. Can you tell me how to get back to Sesame Street?