No record of their physical nature has survived. Except, perhaps, in the form of this characteristic arch.
9 seconds sound clip from the Forbidden Planet (1956) movie soundboard.
You can hear this line at 00:51:17 in the Blu-ray version of the movie.
Quote context
[...]
- I see, that explains the tiger and the deer.
- The heights they had reached.
- I suggest you consider it in comparison to one of our functionally-designed human doorways.
- That recording was made by Krell musicians a half a million years ago.
- Now, if you will follow me, I will show you some of their other remaining artifacts.
[...]
Forbidden Planet (1956) Sound Clip
Actors: Walter Pidgeon (Dr. Edward Morbius), Anne Francis (Altaira "Alta" Morbius), Leslie Nielsen (Commander John J. Adams), Robby the Robot (Marvin Miller)
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