Devon, venturing unknowingly into a quarantine area, is stricken by radiation sickness and is near death when a father-son medical team from a nearby shuttle clinic -- Isolated since the Ark's disaster -- rescue him. They literally bring him back from the dead -- but tell Rachel and Garth that sensitive, sophisticated neuro surgery will be necessary to restore Devon as a reasoning human being. And there is no time or this surgery: the shuttle clinic is about to cast off from the Ark, to answer a distress signal from a nearby planet threatened by a plague. The doctors are persuaded to stay long enough to try the operation -- and while the window for their escape is still open, leave the Ark having restored Devon to life and health.