In this 1906 novel, a comet's mysterious green fog causes a profound transformation of the world. William Leadford, a young Socialist student, seeks both improvements in labor conditions and revenge on the middle-class Nettie for spurning his love. On the evening he plans to kill Nettie, a comet enters the atmosphere and emits a sleep-inducing fog. William awakens to a new world in which he finds peace of mind, peace among nations, and no industrial pollution.