With a budget of about $68,000, it was shot over seven days. All of the interior scenes were shot at sound stages inside Kling Studios. Most of the exterior shots were filmed at Bronson Canyon, a set of caves at Griffith Park in Los Angeles that was a popular location for low-budget films. The exterior scenes of the tracking station were shot at a television station on Mt. Lee, not far from the Hollywood Sign. Screenwriter
Martin Varno said it was the first television station built in Los Angeles, but was only being used for emergency broadcasts when this film was being shot there; it had also been used during World War II to broadcast to allied fores overseas. Varno secured permission to film there simply by calling Los Angeles city officials and asking, something he said nobody else considered trying because they assumed the city would not allow it. Varno was familiar with the station because his father,
Roland Varno, appeared in the first dramatic television show released in Los Angeles and it was transmitted from that station. For this film, Los Angeles charged a fee of $8 per actor to shoot at the station, but the crew could be any size. All shooting took place outside the station. Most of the night scenes shot there were shot during the day, and the crew often had to find shadows to shoot in or block out the sun to give the impression of nighttime. Producer Gene Corman said of the shooting: "That was one of the more mobile units I've ever been involved with. Normally, everybody chases the sun; we were chasing the shadows."
