Jonathan is an only child, he is no longer in contact with his mother, and a deep sense of guilt forces him to return to Earth to look after his father's wellbeing.
Except his father has a secret. He's in poor health and rather confused, so Jonathan finds it hard to get to the bottom of it.
It's not like he has a lot of time, since he has to look for a job, a task which is proving surprisingly hard.
No one wants scientists, especially not if they've worked in space. But his father's secret shows how important it is to keep the work going. Not that governments will listen.