Having recently spent time both on suspended leave from space travel and away from his family, astronaut Tom Antares is sent back out on a solo rescue mission. The victim: his brother Cody, stranded on Io after a freak shuttle malfunction. Upon recovering him, the two start to build up the bridges between them and grow to love each other once again. However, the journey back to Earth is as treacherous as can be what with the very cosmos aiming to resist them. Working their way home and fighting against an unknown disease threatening to claim Cody's life, they begin to piece together the clues as to why they are so far from Earth.Someone led them there, and that someone is now following them.