Thomas and his father Patrick, seemingly ordinary folk, are in fact aliens who must shortly find their spacecraft and leave earth. Like Sylvia Waugh's other creations the Mennyms, they have to keep their real identity a secret. Things go wrong when Patrick is involved in a traffic accident, leaving Thomas to cope with the emergency on his own. There is a clock ticking; will the two be on their spaceship when it leaves in a few days time?As in the Mennyms books, there is a kindly female figure to help them, who might the the author herself(?)and again it is children who realize the truth about the space visitors.Plenty of suspense and a genuine belief in the helpfulness of others.A warm hearted adventure.