Robur (Vincent Price) shoots down a balloon and takes the passengers on board his futuristic flying ship. The prisoners include arms-dealer Prudent (Henry Hull), his daughter Dorothy (Mary Webster), her betrothed Philip Evans (David Frankham), and US Government Agent John Strock (Charles Bronson), all of whom were studying a mysterious volcanic eruption. The eruption was apparently caused by Robur working on his airship, but he had attracted attention by broadcasting a biblical passage over an amplifier, stirring up religious fears and zealotry in nearby Morgantown, Pennsylvania.
The huge ship is called Albatross and Robur is travelling the world over, trying to force world peace on Mankind through superior military power. His crew obey him religiously and all are fanatical idealists. The prisoners gradually learn how the ship operates and how Robur generates power through electrical lines of magnetic force in his shipboard dynamos. Most of the prisoners want to escape, but Strock appears to admire Robur a bit too much. Then Strock saves Evans’ life and shows his true feelings. He is lying to Robur and says he need not behave like a gentleman as he is a captive.
Robur proceeds to destroy the ships and war-machines of various aggressive nations, but the Albatross and Robur himself are damaged in a desert war. The airship escapes and Robur recovers. The ship anchors at an island for repairs and the prisoners rig the armoury to explode, then descend the anchor line. Strock is last and is fired at by the crew when he follows. Strock and Evans cut the anchor line and the damaged ship drifts off until the gunpowder explodes. Robur orders his crew to abandon ship but they gather in his quarters while he reads Bible verses. The former captives stand on the shore and watch the ship crash into the sea.
The film was directed by William Whitney from a screenplay by Richard Matheson. It was produced by Samuel Z. Arkoff, Anthony Carras, and James H. Nicholson, based on Robur the Conqueror and Master of the World by Jules Verne. Robur is a kind of Captain Nemo of the Air, though the similarities are more obvious in the movies than the books. This was Charles Bronson’s first film as a romantic lead. Before, he had always been in a supporting role, usually as a villain. Price thought Bronson was miscast, but Robur was one of his favorite roles. Drawings and models were made for a sequel but that never happened. Lots of archival footage was used. An animated remake was made as a TV movie in 1976.