Leslie and Crow return to their space station after an exploration of lunar ice caves. Upon arrival Crow dies of an unexplained fungus. Faith, the station's biochemist, analyzes the material. After the ship's doctor, Dobson, contracts the infection, he unites with Leslie in telling commander Garland that Earth must be notified. But Garland doesn't want the mission to be disrupted and refuses their request. They go over his head and attempt contact with Earth but are foiled by Curran, the ship's communication officer, who's in love with Garland. The space station runs into a meteor shower which tears a hole in the station's side, causing the mysterious fungus to escape. Dobson concludes that the deadly fungus needs heat to survive, and after Leslie leads a mutiny against Garland, the station is put into a freeze and the fungus killed. By the time of the film's release, space travel was less mysterious than it had been in the genre's heyday 10 years before. Thus this routine fare, with standard production values and acting, was simply too late to stir up much interest.