Travel to other planets is now a reality, and with overpopulation stretching the sources of Earth, the necessity of getting habitable worlds is growing a lot more urgent. There’s a problem though-because the spaceships are slower than light, any communication between the discovering ships and Earth would take years.

Tom and Pat are identical twin teenagers. As twins they’ve always been close, so close it seemed like they could examine each other’s minds. When they are recruited from the Long Range Foundation, the twins find out that they can, certainly, peer into each other’s thoughts. And also other telepathic duos, these are enlisted to become the human transmitters and receivers that may keep the ships in touch with Earth. But there’s a catch: one of the twins has to stay behind-and that one will grow old-while the additional explores the depths of space and earnings still a young man.