The arrival of dynamic new head teacher Karen Fisher heralds a fresh start for the school. Opinionated and ambitious, Karen is determined to bring change, making Waterloo Road a safe and vibrant place to learn. However, Karen's steely exterior masks a deeper fragility as she and her family wrestle with a recent tragedy. Karen's first challenge at the school arrives in the form of the Kirbys – sixth-former Jonah and 13-year-old genius Ruth – who have both been home-schooled by their father, Marcus. Marcus's ex-wife, Hannah, wants her children to experience mainstream schooling, but he has little faith in the state education system. While Jonah relishes the opportunity to make new friends and have new experiences, high-achiever Ruth feels she's got little to learn and soon takes matters into her own hands by running away.