"Chain Reaction" by Boyd Ellanby is a science fiction novella first published in the mid-20th century, specifically in the 1950s. The story revolves around a group of university professors who gather at a sanitarium to visit a colleague, Dr. Rothman, who has been committed after raising alarms about a potential catastrophic chain reaction due to a nuclear test. The narrative explores themes of mental health, scientific ethics, and the consequences of unchecked scientific experimentation. As the plot unfolds, the professors engage in a tense poker game that serves as a backdrop for their discussions about the impending test, which Rothman believes could lead to global annihilation. The story captures the internal struggles and dynamics between the characters, especially as they grapple with doubt and fear surrounding Rothman's calculations. With the clock ticking down to zero hour, the professors' various reactions to the potential end of the world reveal their true character and the weight of their scientific responsibilities. Ultimately, when the test concludes without disaster, Rothman's grip on reality is called into question, leaving the reader to ponder the thin line between genius and madness. (This is an automatically generated summary.)