FLASH GORDON CONQUERS THE UNIVERSE

A deadly plague is ravaging the Earth, known as the Purple Death because of a purple spot left on victims' foreheads. Flash Gordon learns that Ming the Merciless is behind the plague when he spots one of Ming's spaceships spreading the "Death Dust" in the Earth's atmosphere.

Flash Gordon, along with Dr. Alexis Zarkov and Dale Arden, return to the planet Mongo to find a possible cure, first seeking the assistance of their old friend Prince Barin. The trio continues to battle Ming and his allies, led by henchman Captain Torch, who has been charged with stopping the Earthlings by any means.

The three eventually find an antidote, called Polarite, in Mongo's remote northern Kingdom of Frigia. They must now get the cure back to Earth in sufficient quantities to stop the ravaging plague. Ming sends in an army of robot bombs, and he succeeds in capturing Zarkov and Dale. After their capture, Flash must return to Earth to distribute the antidote by rocketship, the same way the original Death Dust was first spread.

Upon his return to Mongo, Flash is able to free Zarkov and Dale. They continue their struggles against Ming, Captain Torch, and his men through a series of close encounters, deadly escapes, and rescues, all the while continuing to thwart Ming and his allies.

Ming and his minions are eventually locked away by one of his men in the high control tower of his castle. Unknown to them, Flash is piloting a rocketship that is speeding directly toward that tower. He parachutes away just in the nick of time, and in a daring aerial maneuver, Flash is successful in boarding Barrin's nearby rocketship, which has Dale and Zarkov aboard. Flash's unmanned spaceship is actually a flying bomb, having been loaded with highly volatile Solarite. Its rapid forward momentum carries it directly into the castle's control tower, where the large explosion that follows ends Ming's tyrannical reign forever. Prince Barin soon takes his rightful place as the peaceful ruler of Mongo.

Ming's last words to Flash were, "I am the universe!" Zarkov observes that with Ming's death, "Flash Gordon has conquered the universe".

Flash loads an unmanned rocket with volatile Solarite and directs it into Ming's castle, ending Ming’s reign. Prince Barin becomes the new ruler of Mongo, and the threat to Earth is neutralized.

The finale cements Flash's role as Earth's savior and brings Ming's tyranny to an explosive close, symbolizing the triumph of courage and alliance over megalomania. With Barin ascending the throne, Mongo is poised for a new era. The destruction of Ming’s control tower marks the literal and figurative breaking of his hold over both worlds.