As Lenny's father goes off to fight in the second world war he gives his son a brass badge with a lion & a unicorn on it. Lenny keeps it with him when bombs are dropped on his street & when he has to be evacuated to a big house in the country. He misses his parents a great deal & the other children there & at school are spiteful in teasing him. But he finds a secret walled garden to escape to with a stone unicorn. Here he meets the wounded soldier Mick & learns again how hard it is to be brave. It is the unicorn who finally rescues him from his sadness & loneliness & proves itself to be his guardian angel by bringing his mother to him.