Ben and Mim find a grandfather in agony with horrific burns after spilling a huge pot of boiling water over himself. Lisa's first day back from maternity leave has her examining a tiny baby with a soaring heart rate and high temperature.

Every second counts as paramedics rush to help people in crisis. A leaking oxygen bottle blows up in a man's face. Nhi and Carlos fear he could stop breathing at any moment. Bill is on high alert, dealing with a violent knife fight.