In the not-too-distant future, mankind has made huge advances in its explorations of the cosmos, establishing scientific stations on many planets. An international project known as Gemini has resulted in the development of a unique planet terraforming unit. But once the unit is launched, Earth loses connection with the carrier rocket transporting the unit outside the Solar System. The unit is lost until a mysterious signal is received from space. It originates on a remote and as-yet uncharted planet. An expedition is sent to the planet itself, to locate the source of the signal. A small group of people – the vanguard of humanity – sets off into the unknown.