Four centuries into the future, Cadets Tom Corbett, Roger Manning and Astro are training to become Solar Guards. Their ship, the "Polaris" took them to numerous adventures, usually natural catastrophes rather than villains.

Set during the middle of the 24th Century at the Space Academy (a training school for the Solar Guards) and aboard the 'Polaris', a Solar Guard training ship, this hugely-popular science-fiction series was one of the very few programs to air on all four major networks, including a brief period in 1951 when it ran on two networks simultaneously (NBC and ABC). It was seen three times weekly over CBS and ABC in fifteen-minute format, and in half-hour episodes on Saturdays over DuMont and NBC.—Hup234!