Eleven-year-old Pearl has always lived on the edges of society Brought up by her mum on a narrow boat, she never went to school and rarely mixed with other people But now her mum is ill in hospital and Pearl has been sent to live with a foster family and there is talk of her being adopted by a forever family All Pearl wants is to be back with her mum on the boat, and when she hears that her mum has absconded from the hospital, she decides to run away back to the boat, where she is sure she will find her