In a lunar research facility, Peter de Hooch awakens from a vivid dream to an emergency call from his colleague, Sam Willows, informing him that Reactor Two has exploded. De Hooch quickly dons his vacuum suit and rushes to the reactor control room, where he learns that two men, Ferguson and Metty, are trapped inside the reactor's anteroom. The reactor is running dangerously with Mercury 203, which is building up towards a catastrophic reaction involving Fermium 256. As De Hooch assesses the situation, he realizes that the reactor lacks a functioning automatic feedback system, making it susceptible to runaway reactions. He and Willows work to stabilize the situation while De Hooch prepares to rescue the trapped men. After successfully retrieving Ferguson and Metty, who are unconscious but alive, De Hooch discovers that the reactor's controls are malfunctioning due to a pressure differential caused by a helium explosion. De Hooch enters the reactor to investigate further, but a sudden pressure release knocks him unconscious. Upon regaining consciousness, he finds himself alone and realizes that the reactor's temperature is rising dangerously. He deduces that the helium production has gone awry, and he must act quickly to prevent a meltdown. In a frantic effort to remove radioactive mercury that has amalgamated with his suit, De Hooch considers various options, ultimately deciding to use the reactor's helium to dissolve the mercury. He enters the reactor chamber, allowing the hot helium to boil off the mercury, risking his own safety in the process. As the situation stabilizes, a rescue team arrives at the facility. They find De Hooch asleep in the control chair, having successfully managed the reactor's crisis. The story concludes with a nod to the nursery rhyme that frames the narrative, emphasizing the cyclical nature of folly and consequence.
By Randall Garrett · First published 1963 · Genre: Science Fiction, Thriller, Adventure