Morris Gleitzman has written these two books, the first is called Once. Once is about a Jewish boy called Felix whose parents have left him in an orphanage. He runs away to find them when the Nazis are invading and it becomes a big adventure. On his way he finds a girl called Zelda and they try to go to the city. But of course they have to get past the Nazis and this is very tricky. Once they are there, a man finds them and he is looking after Jewish children which of course can get him into a lot of trouble. Then Felix discovers that Zelda's parents were Nazis and figures it might help along the way.
Then in the sequel to Once, Zelda and Felix set off into the world alone. Yet again someone finds them and looks after them; she gives them new names Violetta and Wilhelm. With their new identities they manage to keep safe but for how long?
