A young couple, Mark and Katherine, are traveling on a small airplane and are forced to land in a remote town where the people are behaving oddly. They then attempt to escape from the town, but discover that there is a giant glass-like force field bubble around it that prevents anyone from leaving.
The Bubble utilizes many gimmick shots that serve only to showcase the 3-D, which in 1966, after a dozen years' near-total absence from U.S. screens, was once again a novelty interesting in itself. Some gimmicks are marginally plot-related, such as Katherine reaching out to greet her husband, her arms stretching out to the viewer, but many are not. An electrical worker climbs up a power pole, the pole shown from above so that it projects out into the audience. Various objects are thrust out at the viewer. For no logical reason, a tray of beers defies gravity and slowly floats out of the screen to waft about in midair and tantalize the audience for a while before slowly returning. Scenes of vacant-faced townspeople strolling along the sidewalk in a daze while repeatedly opening and closing umbrellas, prolonged beyond any storytelling necessity, are revisited at intervals. Much of this gratuitous footage was trimmed out before later re-releases, unburdening the film of roughly twenty minutes of its original nearly two-hour running time.
The Bubble marked the introduction of the economical Space-Vision 3-D system. Unlike the two-camera, two-projector systems used to make and show the 3-D feature films of the 1950s, Space-Vision used a single ordinary movie camera with an external optical attachment that allowed it to simultaneously photograph the left-eye and right-eye views stacked in an "over-and-under" configuration on a single frame of film. Because each image was only half the standard height, this resulted in a widescreen aspect ratio with roughly the same proportions as CinemaScope. A special attachment on the projector allowed the two images to be projected through oppositely-oriented polarizing filters and superimposed on a screen provided with a special non-depolarizing surface. As with the feature-length 3-D films of the 1950s, the audience had to wear Polaroid-type 3-D glasses so that each eye would see only the image intended for it. Space-Vision was used for Andy Warhol's Frankenstein, the only widely shown 3-D film of the 1970s. Functionally identical over-and-under systems, branded with various names, were used for most of the films made during a revival of 3-D that began with the release of Comin' at Ya! in 1981.
