Bringing the movie out of the screen and into the audience.
http://www.encyclopedia4u.com/b/bwana-devil.html
Bwana Devil was the first full-length color 3-D movie in the United States. It starred Robert Stack and was written and directed by Arch Oboler. It premiered November 27, 1952.
http://home.earthlink.net/~campfire/movies/firsts.html
The first 3D feature with stereophonic sound was Warner Brothers' House of Wax (US '53). When it was premiered at the Paramount Theater, New York, with 25 speakers, the Christian Science Monitor was moved to deplore the "cacophony of sound hurtling relentlessly at one from all directions". André de Toth, director of the movie, may have been able to hear the cacophony, but was unable to see the 3D effect, as he only had one eye.
During the 3D boom that began with the low-budget Bwana Devil (US '52), over 5,000 theaters in the US were equipped to show 3D movies, but the fad was shortlived. 3D production figures were: 1952—1; 1953—27; 1954—16; 1955—1. In addition there were 3D movies produced in Japan, Britain, Mexico, Germany and Hong Kong, but many of these (as well as some of the US productions) were released flat.
http://www.ray3dzone.com/aob.html
screengrabshttp://www.fiftiesweb.com/fashion/3-d-movies.htm
poster, audience wearing 3d-glasseshttp://www.independentfilmsociety.org/gemail091603.html
side-by-side vincent price in wax movie frames/stills