When journalist E. D. Malone is drawn back to the company of Professor Challenger, Professor Summerlee, and Lord John Roxton, a routine errand becomes the prelude to planetary disaster. Challenger's startling letter to The Times warns that changes in the spectra of the stars may signal a vast disturbance in the ether of space, and before long a telegram demanding oxygen turns speculation into immediate alarm. Summoned into a world of confusion, the old companions reunite amid frantic travel, sharp quarrels, and old rivalries. Summerlee derides Challenger's theory as theatrical nonsense, while Malone and Roxton defend him, only to watch their former fellowship crack under pressure. At Challenger's country house, domestic eccentricity gives way to dread as urgent calls reveal that a mysterious, painless death is sweeping across the globe. Then the invisible menace strikes close: the air itself becomes poisonous, crushing breath and strength from the party. Challenger, fierce and brilliant, rescues his unconscious wife, revives the others with oxygen, and turns the crisis into a grim scientific experiment. As he proves his theory right, his hidden tenderness, his wife's spiritual calm, and the group's terror and humiliation deepen the story's suspense in this classic science-fiction tale of cosmic catastrophe, survival, and the limits of human knowledge. This edition has been fully restored with modern typesetting, custom cover design.