On a Friday night, the paramedics are called out to a man who has reportedly collapsed in the street and isn't breathing. Paramedics also treat a man lying unconscious in an alleyway surrounded by needles who's taken a drug overdose but refuses to go to hospital, and a four-year-old who has a high temperature and a nasty cough. On the same shift, a man is struggling to breathe with an abnormal heart rhythm and a woman has fallen and can't get up. The paramedics need to make sure she hasn't broken any bones.

A call comes in from the police saying a young man has collapsed outside a nightclub and isn't breathing. It's a category one emergency - the highest priority - meaning there's an immediate threat to life. A young woman is having a sickle cell crisis. This genetic condition makes her normally round blood cells form a sickle shape, sticking together and causing excruciating pain. A woman has the highest blood pressure that one of the paramedics has ever seen, and she needs to go to hospital urgently. A former soldier collapses and is trapped behind a door, and a woman has crippling chest pains. Her condition is a medical mystery that can only be solved with a trip to A&E.