The Seaview is sent on a mission to receive Man in Space Probe 1, which contains a robot. The project manager, Dr. Raphf Brand, and Admiral Nelson try to access the information contained in the robot without success. When left unattended, the robot breaks out of the lab and kills a crewman. It becomes apparent to the Admiral that the robot was trying to kill every man on board the Seaview. Dr. Brand refuses to admit this, and tries to prove that the robot is still functioning properly. The robot escapes again, and kills more crewmen before it is captured.