Dinah Glass moves in with a new foster family and begins to attend the same school as her new foster brothers. But there is something very strange going on at the school. BBC adaptation of the children's novels by Gillian Cross.

Dinah Glass is a young girl, nervous about joining her new foster family; The Hunters. Although the parents are welcoming, the two brothers (Harvey and Lloyd) are more cautious but that's the least of her problems once she starts at her new school. The headmaster is intent on order and the pupils are unusually willing to obey, except for a few. What is going on and just what is the headmaster up to? Dinah hopes to find out, if she can just win the trust of Harvey and Lloyd.