Planet Krel

Lore & Background

The Krell are a highly advanced race that mysteriously perished in a single night 200,000 years before the events of *Forbidden Planet*. Their underground machine, an 8,000-cubic-mile (33,000 km3) facility powered by 9,208 thermonuclear reactors, could create anything by mere thought anywhere on the planet. Dr. Edward Morbius, a scientist from the earlier expedition, studied Krell artifacts on Altair IV and used an intellect-enhancing device that doubled his mental capacity, though he barely survived the process. The Krell's extinction is explained by Lieutenant Ostrow, who, after using the intellect enhancer, tells Commander Adams that the Krell forgot one thing: 'Monsters from the id.' The machine gave the Krell's own subconscious desires free rein with unlimited power, causing their own extinction. Morbius's own subconscious later creates a creature that kills expedition members and attacks Adams's crew.

In Their Own Story

In the 23rd century, the United Planets starship C-57D arrives at the distant planet Altair IV after more than a year's journey. Dr. Edward Morbius, one of the original expedition's scientists, warns Commander John J. Adams not to land for safety reasons, but Adams ignores his warning. Morbius describes how all other members of their expedition had been killed, one by one, by an unseen 'planetary force,' with the ship *Bellerophon* being vaporized as the last survivors tried to escape. Only Morbius, his wife (who, Morbius claims, later died of natural causes), and their daughter Altaira were somehow immune. An invisible intruder later sabotages communications equipment aboard the starship and brutally murders Chief Engineer Quinn. The creature is detected approaching, and its outline becomes visible when it enters a force field; it kills Lieutenant Farman and two other crewmen. Ostrow uses the Krell intellect enhancer and is fatally injured, but before dying he informs Adams that the underground machine's purpose was to create anything by mere thought, and that the Krell forgot 'Monsters from the id.' Adams deduces that Morbius's subconscious created the creature. Morbius finally accepts the truth and confronts his other self, but is fatally injured. Before dying, he has Adams activate a planetary self-destruct system, and the survivors witness the obliteration of Altair IV.

Reader's Guide

The source focuses entirely on the planet Altair IV and the Krell civilization. For visitors to Altair IV, the source notes that the Krell underground machine is still functioning and can create anything by thought, but it is extremely dangerous. The only human survivors on the planet are Dr. Morbius and his daughter Altaira, who live in a residence served by Robby the Robot. The planet is destroyed at the film's conclusion via a self-destruct system activated by Morbius.

Did You Know?

• The Krell underground machine is 8,000 cubic miles (33,000 km3) and powered by 9,208 thermonuclear reactors.
• The Krell perished in a single night 200,000 years before the events of the film.
• Dr. Morbius used a Krell intellect-enhancing device that doubled his mental capacity, but he barely survived the process.
• The creature that attacks the crew is a manifestation of Morbius's subconscious, created by the Krell machine.
• The planet Altair IV is obliterated at the film's conclusion via a planetary self-destruct system.