As technology has improved nuclear power plants have shrunk to the size that they now be housed in submarines. At the same time rockets were growing larger and larger, till a stage was reached where rockets could be nuclear powered. This lead to the formation of a new agency, the CIFC (Civil Interplanetary Flight Commission)The CIFCs job was to develop newer more efficient rocket motors and alloys to house such motors. Slowly all the obstacles were overcome. Only one factor remained, the human factorWe see an experimental centrifuge designed to test a humans ability to withstand G force acceleration. The experiment is interrupted by Dr Ralph Harrison (Charles Drake) when the potential astronaut passes out The other scientists are frustrated at Harrisons intervention. They were instructed to conduct the tests to the maximum extreme. Harrison goes to the commissioner and hands in his resignation; he declares he wont be party to such unsafe practices.While Harrison is packing to leave Washington he is visited by Prof Nordstrom (Taylor Holmes) he explains he agrees with Harrisons position and is having the same argument with the CIFC Commissioner. Nordstrom has a solution, but wants Harrisons aid to complete it. Harrison agrees with enthusiasmLater at the airport waiting for their flight to California, Nordstrom and Harrison having dinner, discuss various elements of the project, a gentleman a few tables over takes great interest in the conversation before it is interrupted by a nosy news reporter. Harrison argues with the reporter that new speculation is leading to enemy nations learning secrets.The reporter pushes back with the knowledge that it is known why Nordstrom resigned on the verge of the first spaceflight Arriving at a secluded compound, Nordstrom describes to Harrison the various security measures installed. He then introduces his daughter Janice (Karin Booth) and grandson Brian gadge Roberts, (Billy Chapin) Karl, (Franz Roehn) the professors assistant explains the boys father was killed during the Korean War.Later Nordstrom is getting ready for a demonstration. Various US science journalists arrive and are put through a series of elaborate security checks before being allowed to enter.Nordtrom unveils a robot hes built to replace humans on spacecraft. The press challenges Nordstrom about the real value of the robot until the professor explains the robot can be controlled by ESP.Nordstrom further explains that Tobor is sentient and reacts to emotion. He demonstrates this with the help of Janice. He asks her to think thoughts of friendship and the robot responds by offering to shake hands. One of the reporters asks if the robot can read thoughts from strangers. Nordstrom challenges the man to attack Tobor and see what happens. Tobor reacts by defending himself. That concludes the demonstration; the only problem to be overcome is long range communication. A suitable receiver has been completed but the development of a working transmitter has been delayed.Brian cant contain his curiosity anymore. Hed been allowed to listen to the demonstration from his room, but is determined to see the robot in real life. Entering the now demonstration area, Brian finds Tobors controller and gets the robot operational. Something goes wrong and Tobor begins to make menacing advances on the now frightened boy. Brian continues to fight with the control systems trying to deactivate the machine. Torbor responds by going into an uncontrolled frenzy. The robot marches upstairs and destroys a number of items before Brian figures out how to operate the machine and return it to its holding area.As Ralph and Nordstrom begin to clean up the mess they realize there were too many people at the demonstration. 12 were invited but 13 attended. A car leaving the demonstration stops on the side of the road to change the number plates on the car before continuing. Back at the house Ralph is on the phone to the local police giving them the now redundant number plate.Janice questions Ralph about who would be spying on the development of Tobor. He explains that Tobor could easily be reprogrammed as a weapon with destructive patterns, and what would happen if someone produced a few thousand of themFour days later, the chief of the spy ring (Henry Kulky) confers with one of his henchmen. They have been watching the house for days and there is no sign the robot has been moved. They decide they need to break in and steal the technologyIn the Lab, Harrison and Nordstrom have developed a new communication device to telepathically control Tobor. They activate the robot and begin putting it through its paces. First with a simple typing test then follow up with a series of ever more complex navigation exercises ending in Tobor having to deal with a simulated meteor shower. Tobor fails this test and becomes erratic. Nordstrom surmises the machine suffered a mechanical nervous breakdown. They shut the machine down and allow its circuits to cool.Back at the garage in town the spies make their plans to try and steal the technology. They develop a special extending ladder to get over the fence and gain access to the house.Brian is woken by an alarm telling him that intruders are inside the electric fence on the north boundary. Inside the house everyone is aware of the intrusion and watch as the spies get closer. Nordstrom springs his trap and a series of light and sound effects explode through the compound. The spies, thinking they are under attack retreat the way they came.Back at the garage, the spies regroup and begin plan a new approach. They hit on the idea of kidnapping Nordstroms Grandson and use the child to gain access to Tobor. The next day Brian receives an invitation to a science show First Flight To Mars at the planetarium in Los AngelesBrian asks his Grandfather to accompany him, in the meantime Karl has made improvements to Tobors transmitter and it now fits in a pen caseThey arrive at the planetarium and seem puzzled no one else is there, before they can consider their options, the spies introduce themselves then kidnap both menAt the house concern grows. Brian and Nordstrom are now an hour late returning, and military personnel are beginning to arrive at the house for a presentationAt the garage the spies tell them what they expect. And that they will hurt Brian if Nordstrom does not tell the secrets of Tobor. Nordstrom tricks the spies into putting his telepathic transfer device on his head, convincing them it is a hearing aid.He then triggers the transmitter inside his pen. Back at the house the robot becomes functional and begins to go to the rescue of Nordstrom. Ralph realizes what Nordstrom is doing and follows the robot by car after Tobor steals a jeepThe spies become frustrated with Nordstroms delaying tactics and decide to torture the boy a little to convince the professor to get the details right. They then discover the Nordstrom is using his pen as a transmitter and destroy the deviceTobor has stopped cold after the transmitter is destroyed. Ralph considers that if Brian is close enough Tobor might be able to develop a telepathic connection. Reactivating Tobor, the robot springs to life and attacks the spies. He makes quick work of three of the men, but the ring leader escapes by carTobor stops the car, and then renders it inoperable by ripping the hood away and disabling the wiring.The final scene shows a rocket launch with Tobor at the [email protected]