You remember this one: Intrepid astronauts led by Commander John J. Adams (Leslie Nielsen) visit the far-off planet known as Altair-4, where the seemingly idyllic lifestyle enjoyed by reclusive scientist Dr. Edward Morbius (Walter Pidgeon) and his futuristic glam-girl daughter, Altaira Morbius (Anne Francis), is suddenly threatened by the inexplicable rampages of an invisible monster. Few science-fiction films from the '50s remain as popular as this space-opera adaptation of Shakespeare's The Tempest, although we're not sure we agree with the assertion made in one of this deluxe edition’s new documentaries, claiming that Forbidden Planet was the genre's most important pre-Star Wars movie. That appraisal comes from one of the many influential filmmakers who sing Planet's praises in "Exploring the Far Reaches of Forbidden Planet." They include directors Joe Dante, John Landis, and John Carpenter, who are joined by special-effects wizards John Dykstra and Dennis Muren, several film historians, and surviving cast members Leslie Nielsen, Anne Francis, Earl Holliman, and Warren Stevens. Warner excels in the production of special features, and the studio has pulled out all the stops once again, coming up with material that was either believed lost or was just plain forgotten, including test footage from special-effects sequences and lighting comparisons of the various sets. Other featurettes include "Watch the Skies," a Turner Classic Movies documentary on sci-fi films of the '50s, and "Robby the Robot: Engineering a Sci-Fi Icon." Robby stars as well in two 1958 extras: "The Invisible Boy," a feature; and "Robot Client," an episode from the Thin Man TV series.