New science teacher Sue Spark wants to make a good impression on her first day, however she soon discovers that she may have taken on more than she can handle. Her classes quickly descend into chaos, and she soon becomes the subject of many students’ jibes and jokes. The day takes a more serious turn when her pupils manage to lock her in a cupboard, before the fire alarm is set off.

Sue’s fiancé Simon doesn’t want news of their relationship getting out, and is determined to make sure Christine doesn’t find out the truth about the couple. Taking drastic action, Simon suggests Waterloo Road might not be the school for Sue after all. Sensing that it’s make or break time for both her job and her relationship, Sue makes a dodgy deal with Barry Barry.

Meanwhile, budget cuts continue to take their grip over the school. The pupils are frustrated at the closure of the Breakfast Club, and when Connor leads the pupils on a walk-out in protest, Christine has no choice but to threaten her own son and the rest of the class with exclusion.