Seb and his younger brother Bart customarily spend all of their long summer holiday in Spain, with their grandparents. Gradually, as they all become older, relationships are strained, as the old folk try to find things to keep the boys amused. It is not long before the grandfather, Tumbler, who is a retired detective, is using Seb as a trainee investigator to keep tabs on the movements of a sector of the local town who he thinks ‘don’t fit it in’ – they are in fact dwarves of alien origin. Soon, Tumbler and his apprentice are rumbled, and Seb is invited to join a summer campus. Coincidentally, this is run by the dwarves and has only recently been set up, virtually on the Tumbler’s doorstep! At the campus, it gradually becomes apparent that Seb and his classmates have been chosen beforehand, by genetic engineering. They find that they possess special abilities, which have been implanted in them at an early age, and realise that these are now being developed in a matter of weeks. Whatever plans they may have had for the future, their chosen destiny now awaits them.