FLASH GORDON'S TRIP TO MARS

When a mysterious beam of light starts disrupting and destroying the Earth's atmosphere, Flash Gordon (Buster Crabbe), Dr. Zarkov (Frank Shannon), and Dale Arden (Jean Rogers) - accidentally accompanied by wisecracking reporter Happy Hapgood (Donald Kerr) - swing into action in Zarkov's rocketship, believing that it could be coming from the planet Mongo. Once in space, they discover that the ray originates from Mars.

Journeying to the fourth planet, they discover their old enemy from Mongo, Ming the Merciless (Charles B. Middleton), is alive and allied with Azura (Beatrice Roberts), the Witch Queen of Mars. From there, under her protection, he is operating a Nitron ray destroying Earth's atmosphere. Azura can transmute people into living clay, condemned to live and die in darkened caves, and she is hated and feared by most of the population. Conversely, the Clay People, led by their King (Montague Shaw), know how to eliminate Azura's power, but lack the means of escaping the caves to which their ruined bodies restrict them.

Gordon and his party seem to hold the answer to their problem, except that the Clay People do not trust them at first, and end up holding Dale Arden hostage. Ultimately, the Earth visitors and the Clay People become allies in the tandem quest to defeat Azura and stop Ming from destroying the Earth. Flash, Dale, Zarkov, and Hapgood do battle against Azura's magic and her Martian space force, Ming's super-scientific weaponry, the treacherous Forest People, and other dangers on the Red Planet. Finally, they win by the classic strategy of divide-and-conquer, showing Azura that Ming has been plotting behind her back to take power from her.

Azura's alliance with Ming is broken, at the cost of the Queen's own life, but the Clay People are freed from their curse. The evil emperor of Mongo, his Nitron ray destroyed and his escape cut off on all sides by the now hostile Martian forces, is seemingly vanquished by the accidental result of his own machinations and treachery.

The alliance between Ming and Azura is destroyed; Azura dies, the Clay People are freed, and Ming is finally destroyed by his own treachery and with his Nitron ray neutralized, Earth is saved.

Flash and his allies succeed by breaking the unity of their foes, turning Queen Azura against Ming and ending her magical tyranny as well. The climactic defeat of Ming stems directly from his own ambition and duplicity, ultimately leading to his demise at the hands of his failed escape, while the liberation of the Clay People is both a moral and narrative resolution that ties up the many serial threads. The world is restored, and the heroes can finally return home, victorious.