FAQ

A team of astronauts led by Colonel Van Heusen (Kim Spalding) fly to Mars to rescue the previous team, the first manned expedition to Mars, which has become marooned there. They discover a sole survivor, Colonel Edward Carruthers (Marshall Thompson), who swears that his nine fellow crewmen were all killed by an unknown life form during a sandstorm. No one relieves his fantastic story and conclude that Carruthers himself is responsible for murdering them in order to assure his own survival. On the return trip to Earth, however, they realize that the creature has stowed away on board with them.

No. It! The Terror from Beyond Space (henceforth referred to as It!) was based on a screenplay by American science fiction writer Jerome Bixby. It! is said to have been inspired by "Discord in Scarlet", a short story by Canadian-born science fiction writer A.E. Van Vogt, first published in the December 1939 issue of Astounding magazine and included as a novella in von Vogt's science fiction novel The Voyage of the Space Beagle (1950). Both the movie and the short story are said to have provided inspiration for Ridley Scott's 1979 blockbuster film Alien: Das unheimliche Wesen aus einer fremden Welt (1979).

Although filmed in 1958, the story takes place in a futuristic 1973.

Just before leaving Mars, one of the crewmen took some empty crates outside and forgot to close the emergency airlock on his way back in. The shadow of a large humanoid creature is then shown stealing aboard compartment C.

In the movie, Mars is portrayed as a dry planet. Following an autopsy on the body of Joe Kienholz (Thom Carney), Doctor Mary Royce (Ann Doran) determines that the creature sucks the human body dry of every form of liquid: blood, glandular fluid, even his bone marrow. They postulate that this is the way the creature gets its liquid intake.

When Carruthers notices that the oxygen supply in the ship has increased by 40%, he concludes that it is due to the creature's larger lung capacity and that purging the ship of its atmosphere might result in suffocating the creature. He tells Calder (Paul Langton) to lock himself in the airlock and orders the rest of the crew to put on their spacesuits. As It begins breaking into the control room, Carruthers attempts to open the airlock but It prevents him from getting to the release button. In his dying attempt, Heusen manages to flip the switch, and the air is quickly sucked out of the room. Gradually, It stops breathing. Carruthers checks the beast's head, but he appears to be dead. Ann (Shirley Patterson) comes forward to hold Carruthers' hand. In the final scene, a conference is being held back on Earth in which the press is informed about the alien being the true murderer and warned that further exploration of Mars should be bypassed, because "another name for Mars is Death."