The Prince of Space opens in 2131 New York, where hard-bitten reporter Bill Windsor covers the story of the *Helicon*, a sunship found drifting with two hundred passengers dead and drained of blood, its cargo of vitalium looted — an atrocity blamed on the notorious space pirate known only as the Prince of Space. Bill's curiosity about the enigmatic Mr. Cain, a frequent visitor to the mysterious Trainor's Tower, leads to an invitation from Cain himself to meet Dr. Trainor, whose private observatory atop the tower reveals a strange blue-black spot on Mars — evidence, Trainor claims, of an impending Martian invasion tied to the doomed Envers Expedition of decades past. That night, the Prince of Space raids the Tower, abducting Trainor, his daughter Paula, and Cain. Bill later joins Captain Brand's Moon Patrol fleet hunting the pirate, but the nine sunships are ambushed by an azure globe-ship firing devastating atomic projectiles, and all but Bill and Brand are destroyed. The survivors are rescued not by the Patrol but by the Prince's own vessel, the *Red Rover*, and brought to his hidden orbital habitat, the City of Space. There Bill learns that Cain and the Prince are one and the same — a man embittered by past betrayal by a woman, who turned outlaw and now seeks redemption by defending Earth against the true threat: Mars. Trainor, Paula, and the "kidnapped" Cain are revealed as willing allies. The Prince, Brand, Bill, and others destroy a landed Martian scouting party in Mexico, barely surviving the tentacled, blood-draining Martians and their atomic weapons. Unable to convince the skeptical public of the danger, the Prince resorts to piracy again, seizing vitalium from a Patrol convoy to fuel an expedition to Mars itself. Aboard the *Red Rover*, the Prince and Trainor perfect a secret weapon, the vitomaton, which harnesses the vital force of life itself into a self-replicating, matter-consuming green energy. Arriving at Mars, the crew mines the rare metal cerium needed to complete the device, encountering the planet's canals, domed cities, and horrifying use of captive humanoid natives as blood-sport prey — plus the diary of the lost explorer Envers, confirming Earth's first contact ended in tragedy. During the mission, Paula, believing the Prince cannot love her, wanders into the deadly desert to die; the Prince, realizing his own feelings, braves a lethal dust storm and freezing night to save her, with Bill's help, narrowly signaling the departing *Red Rover* back in time. In the climax, the Martians launch their invasion fleet, but the Prince deploys the vitomaton from the *Red Rover*, unleashing living green energy that consumes ship after ship — and ultimately the entire shielded planet of Mars, annihilating it. The novel closes with the Prince and Paula united, the Earth saved and unaware of its rescuer's identity, and Bill returned to civilian life, the reward for the still-unmasked "Prince of Space" now raised to twenty-five million eagles.
By Jack Williamson · First published 1931 · Genre: Science Fiction, Space Opera, Adventure · 8 chapters