It is 1940 and Britain is at war with Germany. Robert has been evacuated from London to his grandparents' farm in Scotland. While exploring the rugged coastline, he finds a boy living in the caves. The boy is called David and he is a Kindertransport child. David had to leave his mother and grandmother behind in Berlin, and has now run away from his cruel foster family nearby.
Meanwhile, at the Gestapo Headquarters in Berlin, it is discovered that an Enigma codebook has been hidden in David's suitcase. A Nazi secret agent in the UK is instructed to find David, retrieve the codebook and kill the boy ...
