Professor Morbius (Walter Pidgeon) 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 Robbie the Robot, while Sycorax is replaced with the powerful race of the Krell. Caliban is represented by the dangerous and invisible "monster from the id", a projection of Morbius' psyche born from the Krell technology instead of Sycorax's womb.