The Tempest two other silent versions, one from 1911 by Edwin Thanhouser, are known to have existed, but have been lost. The plot was adapted for the Western "Yellow Sky", directed by William A. Wellman, in 1946. The 1956 science fiction film "Forbidden Planet" set the story on a planet in space, Altair IV, instead of an island. Professor Morbius and his daughter Altaira (Anne Francis) are the Prospero and Miranda figures (both Prospero and Morbius having harnessed the mighty forces that inhabit their new homes). Ariel is represented by the helpful Robby the Robot, while Sycorax is replaced with the powerful
Forbidden Planet using the great machine as companions ("pets") for his daughter and only outwardly resemble their Earth counterparts. Since the Krell's Great Machine can project matter "in any form" it has the power to create life. Thus, the Krell's self-destruction can be interpreted by the reader as a cosmic punishment for misappropriating the life-creating power of the universe. This is why Commander Adams says in his speech to Altaira "... we are, after all, not God". "Forbidden Planet"s innovative electronic music score, credited as "electronic tonalities", partly to avoid having to pay any of the film industry music guild fees, was