New headmistress Karen Fisher has her hands full dealing with Waterloo Road's newest family - two previously home-schooled pupils, Ruth and Jonah Kirby, and their warring parents. Unhappy attending a mainstream school, Ruth attempts to get expelled from Waterloo Road and when this fails she runs away, inadvertently placing her life in danger.
Chris has his own problems when he discovers the girl he slept with last night is actually one of his new sixth form pupils, Jess Fisher - and she happens to be Karen's daughter.