Mother-and-son relations reach a new low when a row over grades leaves a furious Harry determined to seek revenge on Karen. His method? Wreaking email havoc using Karen's phone. His inflammatory messages to school staff - sent under the guise of his mum - cause a level of fury and paranoia that results in a staffroom revolt. Cesca is particularly paranoid, as one of Harry's mails seems to indicate that Karen knows about her affair with student Jonah. Will this finally put an end to the pair's dangerous fling? And if that weren't enough stress for Karen, she is also contending with the varied demands of Waterloo Road's new business-initiative contest. As the project takes shape, feelings are running high, with Amy and the newly back-to-school Sam battling for authority, while Harry is less than delighted to be paired with the unruly Kyle. Chris has his work cut out as he tries to keep the peace. Elsewhere, it's Tom's first day back since the attack, and his understandable edginess culminates in a violent classroom incident. Here come yet more woes for the school's long-suffering headmistress...
