Jo returns to the UK on a mission to save the Williams family from absolute mayhem. With four children under 10, life is hectic and stressful for mom Natalie and dad Martin. Natalie does the majority of the childcare while Marin sits on the computer and watches her struggle. The strain the kids put on their parents' relationship leaves mom and dad arguing constantly about how to raise them. Natalie is at the breaking point, and Supernanny is her last hope. But it's not only the children who need disciplining--Martin is in for a shock too!