The explorers are launched for Jupiter on a V2 rocket outfitted with nuclear engines, which have just been perfected. On approach to the Jovian system, they are instead contacted by an unidentified male voice and supplied with landing instructions. The team sets down and begins exploring the Earth-like world. Things get more interesting when the three men at the ship decide to return to the settlement and break in, which also allows the creature to enter. After a short confrontation which interrupts an attempted human sacrifice, the creature is felled.