Charles Dennison, a solitary plant biologist and inventor, makes a discovery that could change humanity forever: a drug that comes perilously close to immortality. But before he can patent it, armed strangers confront him on a subway, as if they already know exactly what he carries. What begins as a scientific triumph becomes a breathless urban chase, with Dennison fleeing through the streets while men insist he is the thief and the public is drawn into the confusion. As his briefcase is switched and his identity is called into question, panic drives him to drink his experimental serum in desperation. He is finally trapped by black cars that turn out to be hearses, and his pursuers are revealed as undertakers in disguise. They have seized the drug because they believe the world is not ready for such power, fearing that mass life extension would unleash chaos. Dennison counters that discovery cannot be stopped and that humanity must learn to live with its inventions, setting the stage for a sharp clash between scientific progress and control. This edition has been fully restored with modern typesetting, custom cover design.