13 Ghosts

William Castle: [gimmick] The movie was filmed in "Illusion-O" and a special viewer was needed to see the ghosts. This resulted in a number of sources incorrectly stating that the film was originally shown in 3D. The "ghost viewers" contained a red filter and a blue filter, but unlike 3D viewers/glasses, both eyes would look through the same color filter. The red filter would cause the ghostly images to intensify while the blue filter caused the images to fade.

(at around 44 mins) Dr. Zorba is investigating his dead uncle's bedroom when eerie wind blows through and blows out all the candles. Then one by one the candles relight on the candelabra. One candle floats up on its own from the candelabra with its shadow cast upon the wall. As the candle floats an occasional glimmer of the filament used to "float" the candle can be seen; as the candle returns to its place in the candelabra you can see the shadow of the filament cast upon the wall.

The original version was shot in black and white, but included a few color-tinted sequences. The ghosts were colored in red and shot on a blue background. These sequences were preceded by the message "Use Viewer" and followed by "Remove Viewer". In the prologue, director William Castle explain to the audience how the Illusion-O Ghost Viewer works (for the ghost sequences), while in the epilogue he invites the audience to bring the Ghost Viewer home to try to find more ghosts with it.

Featured in Aweful Movies with Deadly Earnest: 13 Ghosts (1967)