An astronaut crew on their way to the Moon are unexpectedly propelled by gravitational forces and end up on Mars instead.
Astronauts (Lloyd Bridges, Osa Massen, John Emery, Noah Beery, Jr., and Hugh O'Brien) blast off to explore the moon. Because of craft malfunction and some fuel calculations, they end up landing on Mars. On Mars, evidence of a once powerful civilization is found. The scientists determine that an atomic war destroyed most of the Martians (who surprisingly look like humans). Those that survived reverted to a caveman-like existence.—Matthew Soffen <[email protected]>
Space scientists Dr. Ralph Fleming (Morris Ankrum) and Dr. Karl Eckstrom (John Emery) conceive the first manned spaceflight, "Rocketship eXpedition Moon". Eckstrom crews the ship with his brilliant protegé Dr. Lisa Van Horn (Osa Massen), Astronomer Harry Chamberlain (Hugh O'Brien), and engineer Major William Corrigan (Noah Beery Jr.) under pilot Captain Floyd Graham (Lloyd Bridges).
After a succesful launch, the mission goes awry, as the crew are hurled across space and past the moon by a rocket malfunction, to land instead on the planet Mars. Encouraged to explore by Eckstrom, they find the remains of a human civilization destroyed by nuclear warfare. They are soon attacked by a band of savage, mutated humans, and Corrigan and Eckstrom are killed. The survivors escape back into space, but Dr. Van Horn discovers that not enough fuel remains for a safe landing. She and Graham contact Fleming to pass on what they have learned, and share their first and last few tender moments together, before their ship crashes to Earth.
Grief-stricken, and stung by suggestions that the mission was a failure, a sombre Fleming proudly announces the imminent construction of RX-M2...
